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INTEGRATED CIRCUITS
P89C51RC+/P89C51RD+ 80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
Product specification
Replaces 89C51RC+/RD+ of 1999 Apr 01 (see Notes 1 and 2 on page 2) Supersedes data of 1999 Apr 01
1999 Oct 27
IC28 Data Handbook
Philips Semiconductors
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
DESCRIPTION
The 89C51RX+ devices contain a non-volatile FLASH program memory (up to 64 k bytes in the 89C51RD+) that is both parallel programmable and Serial In-System Programmable. In-System Programming allows devices to alter their own program memory, in the actual end product, under software control. This opens up a range of applications that can include the ability to field update the application firmware. A default serial loader (boot loader) program in ROM allows In-System serial programming of the FLASH memory without the need for a loader in the FLASH code. User programs may erase and reprogram the FLASH memory at will through the use of standard routines contained in ROM. These devices are Single-Chip 8-Bit Microcontrollers manufactured in advanced CMOS process and are derivatives of the 80C51 microcontroller family. All the devices have the same instruction set as the 80C51. FLASH/EPROM Memory Size (X by 8) 89C51RC+ 32 k 89C51RD+ 64 k 1024 Yes 512 Yes RAM Size (X by 8) Programmable Timer Counter (PCA)
FEATURES
* 80C51 Central Processing Unit * On-chip FLASH Program Memory with In-System Programming
(ISP) capability
* Boot ROM contains low level FLASH programming routines and a
default serial loader
* Speed up to 33 MHz * Full static operation * RAM expandable externally to 64 k bytes * 4 level priority interrupt * 7 interrupt sources, depending on device * Four 8-bit I/O ports * Full-duplex enhanced UART
- Framing error detection - Automatic address recognition
* Power control modes
- Clock can be stopped and resumed - Idle mode - Power down mode
See P89C51RX2 data sheet for devices which do not require a 12 V programming voltage. The devices also have four 8-bit I/O ports, three 16-bit timer/event counters, a multi-source, four-priority-level, nested interrupt structure, an enhanced UART and on-chip oscillator and timing circuits. For systems that require extra memory capability up to 64 k bytes, each can be expanded using standard TTL-compatible memories and logic. The added features of the P89C51RX+ Family makes them even more powerful microcontrollers for applications that require pulse width modulation, high-speed I/O and up/down counting capabilities such as motor control.
* Programmable clock out * Second DPTR register * Asynchronous port reset * Low EMI (inhibit ALE) * Watchdog timer
ORDERING INFORMATION
MEMORY SIZE 32 k x 8 P89C51RC+IN P89C51RC+IA P89C51RC+IB P89C51RC+JN P89C51RC+JA P89C51RC+JB MEMORY SIZE 64 k x 8 P89C51RD+IN P89C51RD+IA P89C51RD+IB P89C51RD+JN P89C51RD+JA P89C51RD+JB TEMPERATURE RANGE C AND PACKAGE 0 to +70, 40-Pin Plastic Dual In-line Pkg. 0 to +70, 44-Pin Plastic Leaded Chip Carrier 0 to +70, 44-Pin Plastic Quad Flat Pack -40 to +85, 40-Pin Plastic Dual In-line Pkg. -40 to +85, 44-Pin Plastic Leaded Chip Carrier -40 to +85, 44-Pin Plastic Quad Flat Pack VOLTAGE RANGE 5V 5V 5V 5V 5V 5V FREQ. (MHz) 0 to 33 0 to 33 0 to 33 0 to 33 0 to 33 0 to 33 DWG. # SOT129-1 SOT187-2 QFP441 SOT129-1 SOT187-2 QFP441
NOTE: 1. SOT not assigned for this package outline.
1999 Oct 27
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853-2149 22593
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
ORDERING INFORMATION
DEVICE NUMBER (P89C51RC+) P89C51RC+ (FLASH) P89C51RD+ (FLASH) TEMPERATURE RANGE/OPERATING FREQUENCY, MAX (I) I = 33 MHz, 0_C to 70_C J = 33 MHz, -40_C to +85_C PACKAGE (A) A = PLCC B = PQFP N = PDIP
BLOCK DIAGRAM
P0.0-P0.7 P2.0-P2.7
PORT 0 DRIVERS VCC VSS RAM ADDR REGISTER RAM PORT 0 LATCH
PORT 2 DRIVERS
PORT 2 LATCH
FLASH
8 B REGISTER STACK POINTER
ACC
TMP2
TMP1
PROGRAM ADDRESS REGISTER
ALU SFRs TIMERS PSW P.C.A. 8
BUFFER
PC INCREMENTER 16 PROGRAM COUNTER
PSEN ALE EAVPP RST PD TIMING AND CONTROL
INSTRUCTION REGISTER
DPTR'S MULTIPLE
PORT 1 LATCH
PORT 3 LATCH
OSCILLATOR PORT 1 DRIVERS XTAL1 XTAL2 P1.0-P1.7 PORT 3 DRIVERS
P3.0-P3.7
SU01065
1999 Oct 27
3
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
LOGIC SYMBOL
VCC XTAL1 VSS
PLASTIC LEADED CHIP CARRIER PIN FUNCTIONS
6 1 40
7 PORT 0 ADDRESS AND DATA BUS LCC
39
XTAL2 T2 T2EX RST EA/VPP PSEN SECONDARY FUNCTIONS ALE/PROG RxD TxD INT0 INT1 T0 T1 WR RD PORT 1 17 29
18 Pin 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Function NIC* P1.0/T2 P1.1/T2EX P1.2/ECI P1.3/CEX0 P1.4/CEX1 P1.5/CEX2 P1.6/CEX3 P1.7/CEX4 RST P3.0/RxD NIC* P3.1/TxD P3.2/INT0 P3.3/INT1 Pin 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Function P3.4/T0 P3.5/T1 P3.6/WR P3.7/RD XTAL2 XTAL1 VSS NIC* P2.0/A8 P2.1/A9 P2.2/A10 P2.3/A11 P2.4/A12 P2.5/A13 P2.6/A14
28 Pin 31 32 33 34 35 36 37 38 39 40 41 42 43 44 Function P2.7/A15 PSEN ALE NIC* EA/VPP P0.7/AD7 P0.6/AD6 P0.5/AD5 P0.4/AD4 P0.3/AD3 P0.2/AD2 P0.1/AD1 P0.0/AD0 VCC
PORT 3
PORT 2
ADDRESS BUS
SU00830
PIN CONFIGURATIONS DUAL IN-LINE PACKAGE PIN FUNCTIONS
* NO INTERNAL CONNECTION
SU00890
T2/P1.0 1 T2EX/P1.1 2 ECI/P1.2 3 CEX0/P1.3 4 CEX1/P1.4 5 CEX2/P1.5 6 CEX3/P1.6 7 CEX4/P1.7 8 RST 9 RxD/P3.0 10 TxD/P3.1 11 INT0/P3.2 12 INT1/P3.3 13 T0/P3.4 14 T1/P3.5 15 WR/P3.6 16 RD/P3.7 17 XTAL2 18 XTAL1 19 VSS 20 DUAL IN-LINE PACKAGE
40 VCC 39 P0.0/AD0 38 P0.1/AD1 37 P0.2/AD2
PLASTIC QUAD FLAT PACK PIN FUNCTIONS
44 34
1 36 P0.3/AD3 35 P0.4/AD4 34 P0.5/AD5 11 33 P0.6/AD6 32 P0.7/AD7 31 EA/VPP 30 ALE 29 PSEN 28 P2.7/A15 27 P2.6/A14 26 P2.5/A13 25 P2.4/A12 24 P2.3/A11 23 P2.2/A10 22 P2.1/A9 21 P2.0/A8 Pin 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Function P1.5/CEX2 P1.6/CEX3 P1.7/CEX4 RST P3.0/RxD NIC* P3.1/TxD P3.2/INT0 P3.3/INT1 P3.4/T0 P3.5/T1 P3.6/WR P3.7/RD XTAL2 XTAL1 12 Pin 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Function VSS NIC* P2.0/A8 P2.1/A9 P2.2/A10 P2.3/A11 P2.4/A12 P2.5/A13 P2.6/A14 P2.7/A15 PSEN ALE NIC* EA/VPP P0.7/AD7 22 PQFP
33
23
Pin 31 32 33 34 35 36 37 38 39 40 41 42 43 44
Function P0.6/AD6 P0.5/AD5 P0.4/AD4 P0.3/AD3 P0.2/AD2 P0.1/AD1 P0.0/AD0 VCC NIC* P1.0/T2 P1.1/T2EX P1.2/ECI P1.3/CEX0 P1.4/CEX1
* NO INTERNAL CONNECTION
SU00891
SU00888
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4
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
PIN DESCRIPTIONS
PIN NUMBER MNEMONIC VSS VCC P0.0-0.7 DIP 20 40 39-32 LCC 22 44 43-36 QFP 16 38 37-30 TYPE I I I/O NAME AND FUNCTION Ground: 0 V reference. Power Supply: This is the power supply voltage for normal, idle, and power-down operation. Port 0: Port 0 is an open-drain, bidirectional I/O port. Port 0 pins that have 1s written to them float and can be used as high-impedance inputs. Port 0 is also the multiplexed low-order address and data bus during accesses to external program and data memory. In this application, it uses strong internal pull-ups when emitting 1s. Port 1: Port 1 is an 8-bit bidirectional I/O port with internal pull-ups. Port 1 pins that have 1s written to them are pulled high by the internal pull-ups and can be used as inputs. As inputs, port 1 pins that are externally pulled low will source current because of the internal pull-ups. (See DC Electrical Characteristics: IIL). Alternate functions for 89C51RX+ Port 1 include: 1 2 3 4 5 6 7 8 P2.0-P2.7 21-28 2 3 4 5 6 7 8 9 24-31 40 41 42 43 44 1 2 3 18-25 I/O I I I/O I/O I/O I/O I/O I/O T2 (P1.0): Timer/Counter 2 external count input/Clockout (see Programmable Clock-Out) T2EX (P1.1): Timer/Counter 2 Reload/Capture/Direction Control ECI (P1.2): External Clock Input to the PCA CEX0 (P1.3): Capture/Compare External I/O for PCA module 0 CEX1 (P1.4): Capture/Compare External I/O for PCA module 1 CEX2 (P1.5): Capture/Compare External I/O for PCA module 2 CEX3 (P1.6): Capture/Compare External I/O for PCA module 3 CEX4 (P1.7): Capture/Compare External I/O for PCA module 4 Port 2: Port 2 is an 8-bit bidirectional I/O port with internal pull-ups. Port 2 pins that have 1s written to them are pulled high by the internal pull-ups and can be used as inputs. As inputs, port 2 pins that are externally being pulled low will source current because of the internal pull-ups. (See DC Electrical Characteristics: IIL). Port 2 emits the high-order address byte during fetches from external program memory and during accesses to external data memory that use 16-bit addresses (MOVX @DPTR). In this application, it uses strong internal pull-ups when emitting 1s. During accesses to external data memory that use 8-bit addresses (MOV @Ri), port 2 emits the contents of the P2 special function register. Port 3: Port 3 is an 8-bit bidirectional I/O port with internal pull-ups. Port 3 pins that have 1s written to them are pulled high by the internal pull-ups and can be used as inputs. As inputs, port 3 pins that are externally being pulled low will source current because of the pull-ups. (See DC Electrical Characteristics: IIL). Port 3 also serves the special features of the 89C51RX+ family, as listed below: RxD (P3.0): Serial input port TxD (P3.1): Serial output port INT0 (P3.2): External interrupt INT1 (P3.3): External interrupt T0 (P3.4): Timer 0 external input T1 (P3.5): Timer 1 external input WR (P3.6): External data memory write strobe RD (P3.7): External data memory read strobe Reset: A high on this pin for two machine cycles while the oscillator is running, resets the device. An internal resistor to VSS permits a power-on reset using only an external capacitor to VCC. Address Latch Enable: Output pulse for latching the low byte of the address during an access to external memory. In normal operation, ALE is emitted at a constant rate of 1/6 the oscillator frequency, and can be used for external timing or clocking. Note that one ALE pulse is skipped during each access to external data memory. ALE can be disabled by setting SFR auxiliary.0. With this bit set, ALE will be active only during a MOVX instruction.
P1.0-P1.7
1-8
2-9
40-44, 1-3
I/O
P3.0-P3.7
10-17
11, 13-19
5, 7-13
I/O
10 11 12 13 14 15 16 17 RST 9
11 13 14 15 16 17 18 19 10
5 7 8 9 10 11 12 13 4
I O I I I I O O I
ALE
30
33
27
O
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5
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
PIN DESCRIPTIONS (Continued)
PIN NUMBER MNEMONIC PSEN DIP 29 LCC 32 QFP 26 TYPE O NAME AND FUNCTION Program Store Enable: The read strobe to external program memory. When executing code from the external program memory, PSEN is activated twice each machine cycle, except that two PSEN activations are skipped during each access to external data memory. PSEN is not activated during fetches from internal program memory. External Access Enable/Programming Supply Voltage: EA must be externally held low to enable the device to fetch code from external program memory locations 0000H and 7FFFH. If EA is held high, the device executes from internal program memory unless the program counter contains an address greater than 7FFFH for 32 k devices. The value on the EA pin is latched when RST is released and any subsequent changes have no effect. Since the RD+ has 64 k internal memory, the RD+ will execute only from internal memory when EA is held high. This pin also receives the 12.00 V programming supply voltage (VPP) during FLASH programming. Crystal 1: Input to the inverting oscillator amplifier and input to the internal clock generator circuits. Crystal 2: Output from the inverting oscillator amplifier.
EA/VPP
31
35
29
I
XTAL1 XTAL2
19 18
21 20
15 14
I O
NOTE: To avoid "latch-up" effect at power-on, the voltage on any pin (other than VPP) at any time must not be higher than VCC + 0.5 V or VSS - 0.5 V, respectively.
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Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
Table 1. Special Function Registers
SYMBOL ACC* AUXR# AUXR1# 2 B* CCAP0H# CCAP1H# CCAP2H# CCAP3H# CCAP4H# CCAP0L# CCAP1L# CCAP2L# CCAP3L# CCAP4L# CCAPM0# CCAPM1# CCAPM2# CCAPM3# CCAPM4# DESCRIPTION Accumulator Auxiliary Auxiliary 1 B register Module 0 Capture High Module 1 Capture High Module 2 Capture High Module 3 Capture High Module 4 Capture High Module 0 Capture Low Module 1 Capture Low Module 2 Capture Low Module 3 Capture Low Module 4 Capture Low Module 0 Mode Module 1 Mode Module 2 Mode Module 3 Mode Module 4 Mode DIRECT ADDRESS E0H 8EH A2H F0H FAH FBH FCH FDH FEH EAH EBH ECH EDH EEH DAH DBH DCH DDH DEH - - - - - DF CCON*# CH# CL# CMOD# DPTR: DPH DPL IE* IP* IPH# PCA Counter Control PCA Counter High PCA Counter Low PCA Counter Mode Data Pointer (2 bytes) Data Pointer High Data Pointer Low Interrupt Enable Interrupt Priority Interrupt Priority High D8H F9H E9H D9H 83H 82H AF A8H B8H B7H EA BF - B7 - 87 P0* P1* P2* P3* Port 0 Port 1 Port 2 Port 3 80H 90H A0H B0H AD7 97 CEX4 A7 AD15 B7 RD AE EC BE PPC B6 PPCH 86 AD6 96 CEX3 A6 AD14 B6 WR AD ET2 BD PT2 B5 PT2H 85 AD5 95 CEX2 A5 AD13 B5 T1 AC ES BC PS B4 PSH 84 AD4 94 CEX1 A4 AD12 B4 T0 AB ET1 BB PT1 B3 PT1H 83 AD3 93 CEX0 A3 AD11 B3 INT1 AA EX1 BA PX1 B2 PX1H 82 AD2 92 ECI A2 AD10 B2 INT0 A9 ET0 B9 PT0 B1 PT0H 81 AD1 91 T2EX A1 AD9 B1 TxD A8 EX0 B8 PX0 B0 PX0H 80 AD0 90 T2 A0 AD8 B0 RxD FFH FFH FFH FFH x0000000B x0000000B 00H CF ECOM ECOM ECOM ECOM ECOM DE CR CAPP CAPP CAPP CAPP CAPP DD - CAPN CAPN CAPN CAPN CAPN DC CCF4 MAT MAT MAT MAT MAT DB CCF3 TOG TOG TOG TOG TOG DA CCF2 PWM PWM PWM PWM PWM D9 CCF1 ECCF ECCF ECCF ECCF ECCF D8 CCF0 00x00000B 00H 00H 00xxx000B 00H 00H BIT ADDRESS, SYMBOL, OR ALTERNATIVE PORT FUNCTION MSB E7 - - F7 E6 - - F6 E5 -
ENBOOT
LSB E0 AO DPS F0
RESET VALUE 00H xxxxxx00B xx0x00x0B 00H xxxxxxxxB xxxxxxxxB xxxxxxxxB xxxxxxxxB xxxxxxxxB xxxxxxxxB xxxxxxxxB xxxxxxxxB xxxxxxxxB xxxxxxxxB x0000000B x0000000B x0000000B x0000000B x0000000B
E4 - - F4
E3 - GF2 F3
E2 - 0 F2
E1
EXTRAM
- F1
F5
CIDL
WDTE
-
-
-
CPS1
CPS0
ECF
PCON#1 Power Control 87H SMOD1 SMOD0 - POF GF1 GF0 PD IDL 00xxx000B * SFRs are bit addressable. # SFRs are modified from or added to the 80C51 SFRs. - Reserved bits. 1. Reset value depends on reset source. 2. The state of the ENBOOT bit depends on the status byte and PSEN when reset is exited. See the AUXR1 description on page 20.
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Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
Table 1. 89C51RC+/RD+ Special Function Registers (Continued)
SYMBOL DESCRIPTION DIRECT ADDRESS D0H CBH CAH A9H B9H 99H 9F SCON* SP TCON* Serial Control Stack Pointer Timer Control 98H 81H 8F 88H TF1 CF T2CON* T2MOD# TH0 TH1 TH2# TL0 TL1 TL2# TMOD Timer 2 Control Timer 2 Mode Control Timer High 0 Timer High 1 Timer High 2 Timer Low 0 Timer Low 1 Timer Low 2 Timer Mode C8H C9H 8CH 8DH CDH 8AH 8BH CCH 89H GATE C/T M1 M0 GATE C/T M1 M0 TF2 - 8E TR1 CE EXF2 - 8D TF0 CD RCLK - 8C TR0 CC TCLK - 8B IE1 CB EXEN2 - 8A IT1 CA TR2 - 89 IE0 C9 C/T2 T2OE 88 IT0 C8 CP/RL2 DCEN 00H xxxxxx00B 00H 00H 00H 00H 00H 00H 00H 00H
SM0/FE
BIT ADDRESS, SYMBOL, OR ALTERNATIVE PORT FUNCTION MSB LSB D7 D6 AC D5 F0 D4 RS1 D3 RS0 D2 OV D1 - D0 P CY
RESET VALUE 000000x0B 00H 00H 00H 00H xxxxxxxxB
PSW* RACAP2H# RACAP2L# SADDR# SADEN# SBUF
Program Status Word Timer 2 Capture High Timer 2 Capture Low Slave Address Slave Address Mask Serial Data Buffer
9E SM1
9D SM2
9C REN
9B TB8
9A RB8
99 TI
98 RI 00H 07H
WDTRST Watchdog Timer Reset A6H * SFRs are bit addressable. # SFRs are modified from or added to the 80C51 SFRs. - Reserved bits.
OSCILLATOR CHARACTERISTICS
XTAL1 and XTAL2 are the input and output, respectively, of an inverting amplifier. The pins can be configured for use as an on-chip oscillator. To drive the device from an external clock source, XTAL1 should be driven while XTAL2 is left unconnected. There are no requirements on the duty cycle of the external clock signal, because the input to the internal clock circuitry is through a divide-by-two flip-flop. However, minimum and maximum high and low times specified in the data sheet must be observed.
RESET
A reset is accomplished by holding the RST pin high for at least two machine cycles (24 oscillator periods), while the oscillator is running. To insure a good power-on reset, the RST pin must be high long enough to allow the oscillator time to start up (normally a few milliseconds) plus two machine cycles. At power-on, the voltage on VCC and RST must come up at the same time for a proper start-up. Ports 1, 2, and 3 will asynchronously be driven to their reset condition when a voltage above VIH1 (min.) is applied to RESET. The value on the EA pin is latched when RST is deasserted and has no further effect.
1999 Oct 27
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Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
LOW POWER MODES Stop Clock Mode
The static design enables the clock speed to be reduced down to 0 MHz (stopped). When the oscillator is stopped, the RAM and Special Function Registers retain their values. This mode allows step-by-step utilization and permits reduced system power consumption by lowering the clock frequency down to any value. For lowest power consumption the Power Down mode is suggested.
Design Consideration
* When the idle mode is terminated by a hardware reset, the device
normally resumes program execution, from where it left off, up to two machine cycles before the internal reset algorithm takes control. On-chip hardware inhibits access to internal RAM in this event, but access to the port pins is not inhibited. To eliminate the possibility of an unexpected write when Idle is terminated by reset, the instruction following the one that invokes Idle should not be one that writes to a port pin or to external memory.
Idle Mode
In the idle mode (see Table 2), the CPU puts itself to sleep while all of the on-chip peripherals stay active. The instruction to invoke the idle mode is the last instruction executed in the normal operating mode before the idle mode is activated. The CPU contents, the on-chip RAM, and all of the special function registers remain intact during this mode. The idle mode can be terminated either by any enabled interrupt (at which time the process is picked up at the interrupt service routine and continued), or by a hardware reset which starts the processor in the same manner as a power-on reset.
ONCETM Mode
The ONCE ("On-Circuit Emulation") Mode facilitates testing and debugging of systems without the device having to be removed from the circuit. The ONCE Mode is invoked by: 1. Pull ALE low while the device is in reset and PSEN is high; 2. Hold ALE low as RST is deactivated. While the device is in ONCE Mode, the Port 0 pins go into a float state, and the other port pins and ALE and PSEN are weakly pulled high. The oscillator circuit remains active. While the device is in this mode, an emulator or test CPU can be used to drive the circuit. Normal operation is restored when a normal reset is applied.
Power-Down Mode
To save even more power, a Power Down mode (see Table 2) can be invoked by software. In this mode, the oscillator is stopped and the instruction that invoked Power Down is the last instruction executed. The on-chip RAM and Special Function Registers retain their values down to 2.0V and care must be taken to return VCC to the minimum specified operating voltages before the Power Down Mode is terminated. Either a hardware reset or external interrupt can be used to exit from Power Down. Reset redefines all the SFRs but does not change the on-chip RAM. An external interrupt allows both the SFRs and the on-chip RAM to retain their values. To properly terminate Power Down the reset or external interrupt should not be executed before VCC is restored to its normal operating level and must be held active long enough for the oscillator to restart and stabilize (normally less than 10ms). With an external interrupt, INT0 and INT1 must be enabled and configured as level-sensitive. Holding the pin low restarts the oscillator but bringing the pin back high completes the exit. Once the interrupt is serviced, the next instruction to be executed after RETI will be the one following the instruction that put the device into Power Down.
Programmable Clock-Out
A 50% duty cycle clock can be programmed to come out on P1.0. This pin, besides being a regular I/O pin, has two alternate functions. It can be programmed: 1. to input the external clock for Timer/Counter 2, or 2. to output a 50% duty cycle clock ranging from 61 Hz to 4 MHz at a 16 MHz operating frequency. To configure the Timer/Counter 2 as a clock generator, bit C/T2 (in T2CON) must be cleared and bit T20E in T2MOD must be set. Bit TR2 (T2CON.2) also must be set to start the timer. The Clock-Out frequency depends on the oscillator frequency and the reload value of Timer 2 capture registers (RCAP2H, RCAP2L) as shown in this equation: 4 Oscillator Frequency (65536 * RCAP2H, RCAP2L)
Where (RCAP2H,RCAP2L) = the content of RCAP2H and RCAP2L taken as a 16-bit unsigned integer. In the Clock-Out mode Timer 2 roll-overs will not generate an interrupt. This is similar to when it is used as a baud-rate generator. It is possible to use Timer 2 as a baud-rate generator and a clock generator simultaneously. Note, however, that the baud-rate and the Clock-Out frequency will be the same.
POWER OFF FLAG
The Power Off Flag (POF) is set by on-chip circuitry when the VCC level on the 89C51RX+ rises from 0 to 5V. The POF bit can be set or cleared by software allowing a user to determine if the reset is the result of a power-on or a warm start after powerdown. The VCC level must remain above 3V for the POF to remain unaffected by the VCC level.
Table 2. External Pin Status During Idle and Power-Down Mode
MODE Idle Idle Power-down Power-down PROGRAM MEMORY Internal External Internal External ALE 1 1 0 0 PSEN 1 1 0 0 PORT 0 Data Float Data Float PORT 1 Data Data Data Data PORT 2 Data Address Data Data PORT 3 Data Data Data Data
1999 Oct 27
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Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
TIMER 2 OPERATION Timer 2
Timer 2 is a 16-bit Timer/Counter which can operate as either an event timer or an event counter, as selected by C/T2* in the special function register T2CON (see Figure 1). Timer 2 has three operating modes: Capture, Auto-reload (up or down counting), and Baud Rate Generator, which are selected by bits in the T2CON as shown in Table 3.
Figure 3). When reset is applied the DCEN=0 which means Timer 2 will default to counting up. If DCEN bit is set, Timer 2 can count up or down depending on the value of the T2EX pin. Figure 4 shows Timer 2 which will count up automatically since DCEN=0. In this mode there are two options selected by bit EXEN2 in T2CON register. If EXEN2=0, then Timer 2 counts up to 0FFFFH and sets the TF2 (Overflow Flag) bit upon overflow. This causes the Timer 2 registers to be reloaded with the 16-bit value in RCAP2L and RCAP2H. The values in RCAP2L and RCAP2H are preset by software means. If EXEN2=1, then a 16-bit reload can be triggered either by an overflow or by a 1-to-0 transition at input T2EX. This transition also sets the EXF2 bit. The Timer 2 interrupt, if enabled, can be generated when either TF2 or EXF2 are 1. In Figure 5, DCEN=1 which enables Timer 2 to count up or down. This mode allows pin T2EX to control the direction of count. When a logic 1 is applied at pin T2EX Timer 2 will count up. Timer 2 will overflow at 0FFFFH and set the TF2 flag, which can then generate an interrupt, if the interrupt is enabled. This timer overflow also causes the 16-bit value in RCAP2L and RCAP2H to be reloaded into the timer registers TL2 and TH2. When a logic 0 is applied at pin T2EX this causes Timer 2 to count down. The timer will underflow when TL2 and TH2 become equal to the value stored in RCAP2L and RCAP2H. Timer 2 underflow sets the TF2 flag and causes 0FFFFH to be reloaded into the timer registers TL2 and TH2. The external flag EXF2 toggles when Timer 2 underflows or overflows. This EXF2 bit can be used as a 17th bit of resolution if needed. The EXF2 flag does not generate an interrupt in this mode of operation.
Capture Mode
In the capture mode there are two options which are selected by bit EXEN2 in T2CON. If EXEN2=0, then timer 2 is a 16-bit timer or counter (as selected by C/T2* in T2CON) which, upon overflowing sets bit TF2, the timer 2 overflow bit. This bit can be used to generate an interrupt (by enabling the Timer 2 interrupt bit in the IE register). If EXEN2= 1, Timer 2 operates as described above, but with the added feature that a 1- to -0 transition at external input T2EX causes the current value in the Timer 2 registers, TL2 and TH2, to be captured into registers RCAP2L and RCAP2H, respectively. In addition, the transition at T2EX causes bit EXF2 in T2CON to be set, and EXF2 like TF2 can generate an interrupt (which vectors to the same location as Timer 2 overflow interrupt. The Timer 2 interrupt service routine can interrogate TF2 and EXF2 to determine which event caused the interrupt). The capture mode is illustrated in Figure 2 (There is no reload value for TL2 and TH2 in this mode. Even when a capture event occurs from T2EX, the counter keeps on counting T2EX pin transitions or osc/12 pulses.).
Auto-Reload Mode (Up or Down Counter)
In the 16-bit auto-reload mode, Timer 2 can be configured (as either a timer or counter [C/T2* in T2CON]) then programmed to count up or down. The counting direction is determined by bit DCEN (Down Counter Enable) which is located in the T2MOD register (see
(MSB) TF2 Symbol TF2 EXF2 Position T2CON.7 T2CON.6 EXF2 RCLK TCLK EXEN2 TR2 C/T2
(LSB) CP/RL2
Name and Significance Timer 2 overflow flag set by a Timer 2 overflow and must be cleared by software. TF2 will not be set when either RCLK or TCLK = 1. Timer 2 external flag set when either a capture or reload is caused by a negative transition on T2EX and EXEN2 = 1. When Timer 2 interrupt is enabled, EXF2 = 1 will cause the CPU to vector to the Timer 2 interrupt routine. EXF2 must be cleared by software. EXF2 does not cause an interrupt in up/down counter mode (DCEN = 1). Receive clock flag. When set, causes the serial port to use Timer 2 overflow pulses for its receive clock in modes 1 and 3. RCLK = 0 causes Timer 1 overflow to be used for the receive clock. Transmit clock flag. When set, causes the serial port to use Timer 2 overflow pulses for its transmit clock in modes 1 and 3. TCLK = 0 causes Timer 1 overflows to be used for the transmit clock. Timer 2 external enable flag. When set, allows a capture or reload to occur as a result of a negative transition on T2EX if Timer 2 is not being used to clock the serial port. EXEN2 = 0 causes Timer 2 to ignore events at T2EX. Start/stop control for Timer 2. A logic 1 starts the timer. Timer or counter select. (Timer 2) 0 = Internal timer (OSC/12) 1 = External event counter (falling edge triggered). Capture/Reload flag. When set, captures will occur on negative transitions at T2EX if EXEN2 = 1. When cleared, auto-reloads will occur either with Timer 2 overflows or negative transitions at T2EX when EXEN2 = 1. When either RCLK = 1 or TCLK = 1, this bit is ignored and the timer is forced to auto-reload on Timer 2 overflow.
SU00728
RCLK TCLK EXEN2
T2CON.5 T2CON.4 T2CON.3
TR2 C/T2
T2CON.2 T2CON.1
CP/RL2
T2CON.0
Figure 1. Timer/Counter 2 (T2CON) Control Register 1999 Oct 27 10
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
Table 3. Timer 2 Operating Modes
RCLK + TCLK 0 0 1 X CP/RL2 0 1 X X TR2 1 1 1 0 16-bit Auto-reload 16-bit Capture Baud rate generator (off) MODE
OSC
/ 12 C/T2 = 0 TL2 (8-bits) C/T2 = 1 TH2 (8-bits) TF2
T2 Pin
Control
TR2 Transition Detector
Capture Timer 2 Interrupt RCAP2L RCAP2H
T2EX Pin
EXF2
Control
EXEN2
SU00066
Figure 2. Timer 2 in Capture Mode
T2MOD
Address = 0C9H Not Bit Addressable -- Bit 7 -- 6 -- 5 -- 4 -- 3 -- 2 T2OE 1
Reset Value = XXXX XX00B
DCEN 0
Symbol -- T2OE DCEN *
Function Not implemented, reserved for future use.* Timer 2 Output Enable bit. Down Count Enable bit. When set, this allows Timer 2 to be configured as an up/down counter.
User software should not write 1s to reserved bits. These bits may be used in future 8051 family products to invoke new features. In that case, the reset or inactive value of the new bit will be 0, and its active value will be 1. The value read from a reserved bit is indeterminate. Figure 3. Timer 2 Mode (T2MOD) Control Register
SU00729
1999 Oct 27
11
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
OSC
/ 12 C/T2 = 0 TL2 (8-BITS) C/T2 = 1 TH2 (8-BITS)
T2 PIN
CONTROL
TR2
RELOAD
TRANSITION DETECTOR
RCAP2L
RCAP2H TF2 TIMER 2 INTERRUPT
T2EX PIN
EXF2
CONTROL
EXEN2
SU00067
Figure 4. Timer 2 in Auto-Reload Mode (DCEN = 0)
(DOWN COUNTING RELOAD VALUE) FFH FFH
TOGGLE EXF2
OSC
/12
C/T2 = 0 OVERFLOW TL2 TH2 TF2 INTERRUPT
T2 PIN
C/T2 = 1 CONTROL TR2 COUNT DIRECTION 1 = UP 0 = DOWN RCAP2L RCAP2H T2EX PIN
(UP COUNTING RELOAD VALUE)
SU00730
Figure 5. Timer 2 Auto Reload Mode (DCEN = 1)
1999 Oct 27
12
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
Timer 1 Overflow
NOTE: OSC. Freq. is divided by 2, not 12. /2 C/T2 = 0 TL2 (8-bits) C/T2 = 1 T2 Pin Control TH2 (8-bits) "1"
/2 "0" "1" SMOD "0" RCLK
OSC
/ 16 TR2 "1" Reload "0"
RX Clock
TCLK
Transition Detector
RCAP2L
RCAP2H
/ 16
TX Clock
T2EX Pin
EXF2
Timer 2 Interrupt
Control EXEN2 Note availability of additional external interrupt.
SU00068
Figure 6. Timer 2 in Baud Rate Generator Mode
Table 4.
Timer 2 Generated Commonly Used Baud Rates
Timer 2 Osc Freq 12 MHz 12 MHz 12 MHz 12 MHz 12 MHz 12 MHz 12 MHz 6 MHz 6 MHz RCAP2H FF FF FF FF FE FB F2 FD F9 RCAP2L FF D9 B2 64 C8 1E AF 8F 57
The baud rates in modes 1 and 3 are determined by Timer 2's overflow rate given below: Modes 1 and 3 Baud Rates + Timer 2 Overflow Rate 16 The timer can be configured for either "timer" or "counter" operation. In many applications, it is configured for "timer" operation (C/T2*=0). Timer operation is different for Timer 2 when it is being used as a baud rate generator. Usually, as a timer it would increment every machine cycle (i.e., 1/12 the oscillator frequency). As a baud rate generator, it increments every state time (i.e., 1/2 the oscillator frequency). Thus the baud rate formula is as follows: Modes 1 and 3 Baud Rates = Oscillator Frequency [32 [65536 * (RCAP2H, RCAP2L)]] Where: (RCAP2H, RCAP2L)= The content of RCAP2H and RCAP2L taken as a 16-bit unsigned integer. The Timer 2 as a baud rate generator mode shown in Figure 6, is valid only if RCLK and/or TCLK = 1 in T2CON register. Note that a rollover in TH2 does not set TF2, and will not generate an interrupt. Thus, the Timer 2 interrupt does not have to be disabled when Timer 2 is in the baud rate generator mode. Also if the EXEN2 (T2 external enable flag) is set, a 1-to-0 transition in T2EX (Timer/counter 2 trigger input) will set EXF2 (T2 external flag) but will not cause a reload from (RCAP2H, RCAP2L) to (TH2,TL2). Therefore when Timer 2 is in use as a baud rate generator, T2EX can be used as an additional external interrupt, if needed.
Ba d Rate Baud 375 K 9.6 K 2.8 K 2.4 K 1.2 K 300 110 300 110
Baud Rate Generator Mode
Bits TCLK and/or RCLK in T2CON (Table 4) allow the serial port transmit and receive baud rates to be derived from either Timer 1 or Timer 2. When TCLK= 0, Timer 1 is used as the serial port transmit baud rate generator. When TCLK= 1, Timer 2 is used as the serial port transmit baud rate generator. RCLK has the same effect for the serial port receive baud rate. With these two bits, the serial port can have different receive and transmit baud rates - one generated by Timer 1, the other by Timer 2. Figure 6 shows the Timer 2 in baud rate generation mode. The baud rate generation mode is like the auto-reload mode,in that a rollover in TH2 causes the Timer 2 registers to be reloaded with the 16-bit value in registers RCAP2H and RCAP2L, which are preset by software.
1999 Oct 27
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Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
When Timer 2 is in the baud rate generator mode, one should not try to read or write TH2 and TL2. As a baud rate generator, Timer 2 is incremented every state time (osc/2) or asynchronously from pin T2; under these conditions, a read or write of TH2 or TL2 may not be accurate. The RCAP2 registers may be read, but should not be written to, because a write might overlap a reload and cause write and/or reload errors. The timer should be turned off (clear TR2) before accessing the Timer 2 or RCAP2 registers. Table 4 shows commonly used baud rates and how they can be obtained from Timer 2.
If Timer 2 is being clocked internally , the baud rate is: Baud Rate + f OSC [65536 * (RCAP2H, RCAP2L)]]
[32
Where fOSC= Oscillator Frequency To obtain the reload value for RCAP2H and RCAP2L, the above equation can be rewritten as: RCAP2H, RCAP2L + 65536 * f OSC Baud Rate
32
Summary of Baud Rate Equations
Timer 2 is in baud rate generating mode. If Timer 2 is being clocked through pin T2(P1.0) the baud rate is: Baud Rate + Timer 2 Overflow Rate 16
Timer/Counter 2 Set-up
Except for the baud rate generator mode, the values given for T2CON do not include the setting of the TR2 bit. Therefore, bit TR2 must be set, separately, to turn the timer on. see Table 5 for set-up of Timer 2 as a timer. Also see Table 6 for set-up of Timer 2 as a counter.
Table 5.
Timer 2 as a Timer
T2CON MODE INTERNAL CONTROL (Note 1) 00H 01H 34H 24H 14H EXTERNAL CONTROL (Note 2) 08H 09H 36H 26H 16H
16-bit Auto-Reload 16-bit Capture Baud rate generator receive and transmit same baud rate Receive only Transmit only
Table 6.
Timer 2 as a Counter
TMOD MODE INTERNAL CONTROL (Note 1) 02H 03H EXTERNAL CONTROL (Note 2) 0AH 0BH
16-bit Auto-Reload
NOTES: 1. Capture/reload occurs only on timer/counter overflow. 2. Capture/reload occurs on timer/counter overflow and a 1-to-0 transition on T2EX (P1.1) pin except when Timer 2 is used in the baud rate generator mode.
1999 Oct 27
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Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
Enhanced UART
The UART operates in all of the usual modes that are described in the first section of Data Handbook IC20, 80C51-Based 8-Bit Microcontrollers. In addition the UART can perform framing error detect by looking for missing stop bits, and automatic address recognition. The UART also fully supports multiprocessor communication as does the standard 80C51 UART. When used for framing error detect the UART looks for missing stop bits in the communication. A missing bit will set the FE bit in the SCON register. The FE bit shares the SCON.7 bit with SM0 and the function of SCON.7 is determined by PCON.6 (SMOD0) (see Figure 7). If SMOD0 is set then SCON.7 functions as FE. SCON.7 functions as SM0 when SMOD0 is cleared. When used as FE SCON.7 can only be cleared by software. Refer to Figure 8. Automatic Address Recognition Automatic Address Recognition is a feature which allows the UART to recognize certain addresses in the serial bit stream by using hardware to make the comparisons. This feature saves a great deal of software overhead by eliminating the need for the software to examine every serial address which passes by the serial port. This feature is enabled by setting the SM2 bit in SCON. In the 9 bit UART modes, mode 2 and mode 3, the Receive Interrupt flag (RI) will be automatically set when the received byte contains either the "Given" address or the "Broadcast" address. The 9 bit mode requires that the 9th information bit is a 1 to indicate that the received information is an address and not data. Automatic address recognition is shown in Figure 9. The 8 bit mode is called Mode 1. In this mode the RI flag will be set if SM2 is enabled and the information received has a valid stop bit following the 8 address bits and the information is either a Given or Broadcast address. Mode 0 is the Shift Register mode and SM2 is ignored. Using the Automatic Address Recognition feature allows a master to selectively communicate with one or more slaves by invoking the Given slave address or addresses. All of the slaves may be contacted by using the Broadcast address. Two special Function Registers are used to define the slave's address, SADDR, and the address mask, SADEN. SADEN is used to define which bits in the SADDR are to b used and which bits are "don't care". The SADEN mask can be logically ANDed with the SADDR to create the "Given" address which the master will use for addressing each of the slaves. Use of the Given address allows multiple slaves to be recognized while excluding others. The following examples will help to show the versatility of this scheme: Slave 0 SADDR = SADEN = Given = 1100 0000 1111 1101 1100 00X0
Slave 1
SADDR = SADEN = Given =
1100 0000 1111 1110 1100 000X
In the above example SADDR is the same and the SADEN data is used to differentiate between the two slaves. Slave 0 requires a 0 in bit 0 and it ignores bit 1. Slave 1 requires a 0 in bit 1 and bit 0 is ignored. A unique address for Slave 0 would be 1100 0010 since slave 1 requires a 0 in bit 1. A unique address for slave 1 would be 1100 0001 since a 1 in bit 0 will exclude slave 0. Both slaves can be selected at the same time by an address which has bit 0 = 0 (for slave 0) and bit 1 = 0 (for slave 1). Thus, both could be addressed with 1100 0000. In a more complex system the following could be used to select slaves 1 and 2 while excluding slave 0: Slave 0 SADDR = SADEN = Given = SADDR = SADEN = Given = SADDR = SADEN = Given = 1100 0000 1111 1001 1100 0XX0 1110 0000 1111 1010 1110 0X0X 1110 0000 1111 1100 1110 00XX
Slave 1
Slave 2
In the above example the differentiation among the 3 slaves is in the lower 3 address bits. Slave 0 requires that bit 0 = 0 and it can be uniquely addressed by 1110 0110. Slave 1 requires that bit 1 = 0 and it can be uniquely addressed by 1110 and 0101. Slave 2 requires that bit 2 = 0 and its unique address is 1110 0011. To select Slaves 0 and 1 and exclude Slave 2 use address 1110 0100, since it is necessary to make bit 2 = 1 to exclude slave 2. The Broadcast Address for each slave is created by taking the logical OR of SADDR and SADEN. Zeros in this result are trended as don't-cares. In most cases, interpreting the don't-cares as ones, the broadcast address will be FF hexadecimal. Upon reset SADDR (SFR address 0A9H) and SADEN (SFR address 0B9H) are leaded with 0s. This produces a given address of all "don't cares" as well as a Broadcast address of all "don't cares". This effectively disables the Automatic Addressing mode and allows the microcontroller to use standard 80C51 type UART drivers which do not make use of this feature.
1999 Oct 27
15
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
SCON Address = 98H Bit Addressable SM0/FE Bit: SM1 SM2 5 REN 4 TB8 3 RB8 2 Tl 1 Rl 0
Reset Value = 0000 0000B
7 6 (SMOD0 = 0/1)*
Symbol FE SM0 SM1
Function Framing Error bit. This bit is set by the receiver when an invalid stop bit is detected. The FE bit is not cleared by valid frames but should be cleared by software. The SMOD0 bit must be set to enable access to the FE bit. Serial Port Mode Bit 0, (SMOD0 must = 0 to access bit SM0) Serial Port Mode Bit 1 SM0 SM1 Mode 0 0 1 1 0 1 0 1 0 1 2 3 Description shift register 8-bit UART 9-bit UART 9-bit UART Baud Rate** fOSC/12 variable fOSC/64 or fOSC/32 variable
SM2
Enables the Automatic Address Recognition feature in Modes 2 or 3. If SM2 = 1 then Rl will not be set unless the received 9th data bit (RB8) is 1, indicating an address, and the received byte is a Given or Broadcast Address. In Mode 1, if SM2 = 1 then Rl will not be activated unless a valid stop bit was received, and the received byte is a Given or Broadcast Address. In Mode 0, SM2 should be 0. Enables serial reception. Set by software to enable reception. Clear by software to disable reception. The 9th data bit that will be transmitted in Modes 2 and 3. Set or clear by software as desired. In modes 2 and 3, the 9th data bit that was received. In Mode 1, if SM2 = 0, RB8 is the stop bit that was received. In Mode 0, RB8 is not used. Transmit interrupt flag. Set by hardware at the end of the 8th bit time in Mode 0, or at the beginning of the stop bit in the other modes, in any serial transmission. Must be cleared by software. Receive interrupt flag. Set by hardware at the end of the 8th bit time in Mode 0, or halfway through the stop bit time in the other modes, in any serial reception (except see SM2). Must be cleared by software.
REN TB8 RB8 Tl Rl
NOTE: *SMOD0 is located at PCON6. **fOSC = oscillator frequency
SU00043
Figure 7. SCON: Serial Port Control Register
1999 Oct 27
16
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
D0
D1
D2
D3
D4
D5
D6
D7
D8
START BIT
DATA BYTE
ONLY IN MODE 2, 3
STOP BIT
SET FE BIT IF STOP BIT IS 0 (FRAMING ERROR) SM0 TO UART MODE CONTROL
SM0 / FE
SM1
SM2
REN
TB8
RB8
TI
RI
SCON (98H)
SMOD1
SMOD0
-
POF
GF1
GF0
PD
IDL
PCON (87H)
0 : SCON.7 = SM0 1 : SCON.7 = FE
SU01191
Figure 8. UART Framing Error Detection
D0
D1
D2
D3
D4
D5
D6
D7
D8
SM0 1 1
SM1 1 0
SM2 1
REN 1
TB8 X
RB8
TI
RI
SCON (98H)
RECEIVED ADDRESS D0 TO D7 PROGRAMMED ADDRESS COMPARATOR
IN UART MODE 2 OR MODE 3 AND SM2 = 1: INTERRUPT IF REN=1, RB8=1 AND "RECEIVED ADDRESS" = "PROGRAMMED ADDRESS" - WHEN OWN ADDRESS RECEIVED, CLEAR SM2 TO RECEIVE DATA BYTES - WHEN ALL DATA BYTES HAVE BEEN RECEIVED: SET SM2 TO WAIT FOR NEXT ADDRESS.
SU00045
Figure 9. UART Multiprocessor Communication, Automatic Address Recognition
1999 Oct 27
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Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
Interrupt Priority Structure
The 89C51RC+/RD+ have a 7-source four-level interrupt structure (see Table 7). There are 3 SFRs associated with the four-level interrupt. They are the IE, IP, and IPH. (See Figures 10, 11, and 12.) The IPH (Interrupt Priority High) register makes the four-level interrupt structure possible. The IPH is located at SFR address B7H. The structure of the IPH register and a description of its bits is shown in Figure 12. The function of the IPH SFR, when combined with the IP SFR, determines the priority of each interrupt. The priority of each interrupt is determined as shown in the following table: PRIORITY BITS IPH.x 0 0 1 1 IP.x 0 1 0 1 INTERRUPT PRIORITY LEVEL Level 0 (lowest priority) Level 1 Level 2 Level 3 (highest priority)
The priority scheme for servicing the interrupts is the same as that for the 80C51. There are four interrupt levels. An interrupt will be serviced as long as an interrupt of equal or higher priority is not already being serviced. If an interrupt of equal or higher level priority is being serviced, the new interrupt will wait until it is finished before being serviced. If a lower priority level interrupt is being serviced, it will be stopped and the new interrupt serviced. When the new interrupt is finished, the lower priority level interrupt that was stopped will be completed.
Table 7.
Interrupt Table
POLLING PRIORITY 1 2 3 4 5 6 7 REQUEST BITS IE0 TP0 IE1 TF1 CF, CCFn n = 0-4 RI, TI TF2, EXF2 HARDWARE CLEAR? N (L)1 Y N (L) Y (T) Y N N N Y (T)2 VECTOR ADDRESS 03H 0BH 13H 1BH 33H 23H 2BH X0 T0 X1 T1 PCA SP T2
SOURCE
NOTES: 1. L = Level activated 2. T = Transition activated 7 IE (0A8H) EA 6 EC 5 ET2 4 ES 3 ET1 2 EX1 1 ET0 0 EX0
Enable Bit = 1 enables the interrupt. Enable Bit = 0 disables it. BIT IE.7 IE.6 IE.5 IE.4 IE.3 IE.2 IE.1 IE.0 SYMBOL EA EC ET2 ES ET1 EX1 ET0 EX0 FUNCTION Global disable bit. If EA = 0, all interrupts are disabled. If EA = 1, each interrupt can be individually enabled or disabled by setting or clearing its enable bit. PCA interrupt enable bit Timer 2 interrupt enable bit. Serial Port interrupt enable bit. Timer 1 interrupt enable bit. External interrupt 1 enable bit. Timer 0 interrupt enable bit. External interrupt 0 enable bit.
SU01037
Figure 10. IE Registers
1999 Oct 27
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Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
7 IP (0B8H) --
6 PPC
5 PT2
4 PS
3 PT1
2 PX1
1 PT0
0 PX0
Priority Bit = 1 assigns high priority Priority Bit = 0 assigns low priority BIT IP.7 IP.6 IP.5 IP.4 IP.3 IP.2 IP.1 IP.0 SYMBOL -- PPC PT2 PS PT1 PX1 PT0 PX0 FUNCTION Not implemented, reserved for future use. PCA interrupt priority bit Timer 2 interrupt priority bit. Serial Port interrupt priority bit. Timer 1 interrupt priority bit. External interrupt 1 priority bit. Timer 0 interrupt priority bit. External interrupt 0 priority bit. Figure 11. IP Registers
SU01038
7 IPH (B7H) --
6 PPCH
5 PT2H
4 PSH
3 PT1H
2 PX1H
1 PT0H
0 PX0H
Priority Bit = 1 assigns higher priority Priority Bit = 0 assigns lower priority BIT IPH.7 IPH.6 IPH.5 IPH.4 IPH.3 IPH.2 IPH.1 IPH.0 SYMBOL -- PPCH PT2H PSH PT1H PX1H PT0H PX0H FUNCTION Not implemented, reserved for future use. PCA interrupt priority bit Timer 2 interrupt priority bit high. Serial Port interrupt priority bit high. Timer 1 interrupt priority bit high. External interrupt 1 priority bit high. Timer 0 interrupt priority bit high. External interrupt 0 priority bit high. Figure 12. IPH Registers
SU01039
1999 Oct 27
19
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
Reduced EMI Mode
The AO bit (AUXR.0) in the AUXR register when set disables the ALE output.
be quickly toggled simply by executing an INC AUXR1 instruction without affecting the GF2 bit. The ENBOOT bit determines whether the BOOTROM is enabled or disabled. This bit will automatically be set if the status byte is non zero during reset or PSEN is pulled low, ALE floats high, and EA > VIH on the falling edge of reset. Otherwise, this bit will be cleared during reset.
Reduced EMI Mode
AUXR (8EH)
7 - 6 - 5 - 4 - 3 - 2 - 1 EXTRAM 0 AO
AUXR.1 AUXR.0
EXTRAM AO
Turns off ALE output.
DPS BIT0 AUXR1
DPTR1 DPTR0 DPH (83H) DPL (82H) EXTERNAL DATA MEMORY
Dual DPTR
The dual DPTR structure (see Figure 13) is a way by which the chip will specify the address of an external data memory location. There are two 16-bit DPTR registers that address the external memory, and a single bit called DPS = AUXR1/bit0 that allows the program code to switch between them.
SU00745A
* New Register Name: AUXR1# * SFR Address: A2H * Reset Value: xx0x00x0B
AUXR1 (A2H)
7 - 6 - 5 ENBOOT 4 -
Figure 13.
DPTR Instructions The instructions that refer to DPTR refer to the data pointer that is currently selected using the AUXR1/bit 0 register. The six instructions that use the DPTR are as follows:
3 GF2 2 0 1 - 0 DPS
INC DPTR MOV DPTR, #data16 MOV A, @ A+DPTR MOVX A, @ DPTR MOVX @ DPTR , A JMP @ A + DPTR
Increments the data pointer by 1 Loads the DPTR with a 16-bit constant Move code byte relative to DPTR to ACC Move external RAM (16-bit address) to ACC Move ACC to external RAM (16-bit address) Jump indirect relative to DPTR
Where: DPS = AUXR1/bit0 = Switches between DPTR0 and DPTR1. Select Reg DPTR0 DPTR1 DPS 0 1
The DPS bit status should be saved by software when switching between DPTR0 and DPTR1. The GF2 bit is a general purpose user-defined flag. Note that bit 2 is not writable and is always read as a zero. This allows the DPS bit to
The data pointer can be accessed on a byte-by-byte basis by specifying the low or high byte in an instruction which accesses the SFRs. See application note AN458 for more details.
1999 Oct 27
20
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
Programmable Counter Array (PCA)
The Programmable Counter Array, available on the 89C51RX+, is a special 16-bit Timer that has five 16-bit capture/compare modules associated with it. Each of the modules can be programmed to operate in one of four modes: rising and/or falling edge capture, software timer, high-speed output, or pulse width modulator. Each module has a pin associated with it in port 1. Module 0 is connected to P1.3(CEX0), module 1 to P1.4(CEX1), etc. The basic PCA configuration is shown in Figure 14. The PCA timer is a common time base for all five modules and can be programmed to run at: 1/12 the oscillator frequency, 1/4 the oscillator frequency, the Timer 0 overflow, or the input on the ECI pin (P1.2). The timer count source is determined from the CPS1 and CPS0 bits in the CMOD SFR as follows (see Figure 17): CPS1 CPS0 PCA Timer Count Source 0 0 1/12 oscillator frequency 0 1 1/4 oscillator frequency 1 0 Timer 0 overflow 1 1 External Input at ECI pin In the CMOD SFR are three additional bits associated with the PCA. They are CIDL which allows the PCA to stop during idle mode, WDTE which enables or disables the watchdog function on module 4, and ECF which when set causes an interrupt and the PCA overflow flag CF (in the CCON SFR) to be set when the PCA timer overflows. These functions are shown in Figure 15. The watchdog timer function is implemented in module 4 (see Figure 24). The CCON SFR contains the run control bit for the PCA and the flags for the PCA timer (CF) and each module (refer to Figure 18). To run the PCA the CR bit (CCON.6) must be set by software. The PCA is shut off by clearing this bit. The CF bit (CCON.7) is set when the PCA counter overflows and an interrupt will be generated if the
ECF bit in the CMOD register is set, The CF bit can only be cleared by software. Bits 0 through 4 of the CCON register are the flags for the modules (bit 0 for module 0, bit 1 for module 1, etc.) and are set by hardware when either a match or a capture occurs. These flags also can only be cleared by software. The PCA interrupt system shown in Figure 16. Each module in the PCA has a special function register associated with it. These registers are: CCAPM0 for module 0, CCAPM1 for module 1, etc. (see Figure 19). The registers contain the bits that control the mode that each module will operate in. The ECCF bit (CCAPMn.0 where n=0, 1, 2, 3, or 4 depending on the module) enables the CCF flag in the CCON SFR to generate an interrupt when a match or compare occurs in the associated module. PWM (CCAPMn.1) enables the pulse width modulation mode. The TOG bit (CCAPMn.2) when set causes the CEX output associated with the module to toggle when there is a match between the PCA counter and the module's capture/compare register. The match bit MAT (CCAPMn.3) when set will cause the CCFn bit in the CCON register to be set when there is a match between the PCA counter and the module's capture/compare register. The next two bits CAPN (CCAPMn.4) and CAPP (CCAPMn.5) determine the edge that a capture input will be active on. The CAPN bit enables the negative edge, and the CAPP bit enables the positive edge. If both bits are set both edges will be enabled and a capture will occur for either transition. The last bit in the register ECOM (CCAPMn.6) when set enables the comparator function. Figure 20 shows the CCAPMn settings for the various PCA functions. There are two additional registers associated with each of the PCA modules. They are CCAPnH and CCAPnL and these are the registers that store the 16-bit count when a capture occurs or a compare should occur. When a module is used in the PWM mode these registers are used to control the duty cycle of the output.
16 BITS MODULE 0 P1.3/CEX0
MODULE 1 16 BITS PCA TIMER/COUNTER TIME BASE FOR PCA MODULES MODULE 3 MODULE FUNCTIONS: 16-BIT CAPTURE 16-BIT TIMER 16-BIT HIGH SPEED OUTPUT 8-BIT PWM WATCHDOG TIMER (MODULE 4 ONLY) MODULE 2
P1.4/CEX1
P1.5/CEX2
P1.6/CEX3
MODULE 4
P1.7/CEX4
SU00032
Figure 14. Programmable Counter Array (PCA)
1999 Oct 27
21
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
OSC/12
TO PCA MODULES
OSC/4 CH TIMER 0 OVERFLOW EXTERNAL INPUT (P1.2/ECI) 00 01 10 11 CL
OVERFLOW INTERRUPT
16-BIT UP COUNTER
DECODE
IDLE CIDL WDTE -- -- -- CPS1 CPS0 ECF CMOD (D9H)
CF
CR
--
CCF4
CCF3
CCF2
CCF1
CCF0
CCON (D8H)
SU00033
Figure 15. PCA Timer/Counter
CF PCA TIMER/COUNTER
CR
--
CCF4
CCF3
CCF2
CCF1
CCF0
CCON (D8H)
MODULE 0 IE.6 EC MODULE 1 IE.7 EA TO INTERRUPT PRIORITY DECODER
MODULE 2
MODULE 3
MODULE 4
CMOD.0
ECF
CCAPMn.0
ECCFn
SU00034
Figure 16. PCA Interrupt System
1999 Oct 27
22
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
CMOD Address = OD9H
Reset Value = 00XX X000B
CIDL Bit: Symbol CIDL WDTE - CPS1 CPS0 Function 7
WDTE 6
- 5
- 4
- 3
CPS1 2
CPS0 1
ECF 0
Counter Idle control: CIDL = 0 programs the PCA Counter to continue functioning during idle Mode. CIDL = 1 programs it to be gated off during idle. Watchdog Timer Enable: WDTE = 0 disables Watchdog Timer function on PCA Module 4. WDTE = 1 enables it. Not implemented, reserved for future use.* PCA Count Pulse Select bit 1. PCA Count Pulse Select bit 0. CPS1 CPS0 Selected PCA Input** 0 0 1 1 0 1 0 1 0 1 2 3 Internal clock, fOSC / 12 Internal clock, fOSC / 4 Timer 0 overflow External clock at ECI/P1.2 pin (max. rate = fOSC / 8)
ECF
PCA Enable Counter Overflow interrupt: ECF = 1 enables CF bit in CCON to generate an interrupt. ECF = 0 disables that function of CF.
NOTE: * User software should not write 1s to reserved bits. These bits may be used in future 8051 family products to invoke new features. In that case, the reset or inactive value of the new bit will be 0, and its active value will be 1. The value read from a reserved bit is indeterminate. ** fOSC = oscillator frequency
SU00035
Figure 17. CMOD: PCA Counter Mode Register
CCON Address = OD8H Bit Addressable CF Bit: Symbol CF CR - CCF4 CCF3 CCF2 CCF1 CCF0 Function 7 CR 6 - 5 CCF4 4 CCF3 3 CCF2 2 CCF1 1 CCF0 0
Reset Value = 00X0 0000B
PCA Counter Overflow flag. Set by hardware when the counter rolls over. CF flags an interrupt if bit ECF in CMOD is set. CF may be set by either hardware or software but can only be cleared by software. PCA Counter Run control bit. Set by software to turn the PCA counter on. Must be cleared by software to turn the PCA counter off. Not implemented, reserved for future use*. PCA Module 4 interrupt flag. Set by hardware when a match or capture occurs. Must be cleared by software. PCA Module 3 interrupt flag. Set by hardware when a match or capture occurs. Must be cleared by software. PCA Module 2 interrupt flag. Set by hardware when a match or capture occurs. Must be cleared by software. PCA Module 1 interrupt flag. Set by hardware when a match or capture occurs. Must be cleared by software. PCA Module 0 interrupt flag. Set by hardware when a match or capture occurs. Must be cleared by software.
NOTE: * User software should not write 1s to reserved bits. These bits may be used in future 8051 family products to invoke new features. In that case, the reset or inactive value of the new bit will be 0, and its active value will be 1. The value read from a reserved bit is indeterminate.
SU00036
Figure 18. CCON: PCA Counter Control Register
1999 Oct 27
23
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
CCAPMn Address
CCAPM0 CCAPM1 CCAPM2 CCAPM3 CCAPM4
0DAH 0DBH 0DCH 0DDH 0DEH
Reset Value = X000 0000B
Not Bit Addressable - Bit: Symbol - ECOMn CAPPn CAPNn MATn TOGn PWMn ECCFn Function Not implemented, reserved for future use*. Enable Comparator. ECOMn = 1 enables the comparator function. Capture Positive, CAPPn = 1 enables positive edge capture. Capture Negative, CAPNn = 1 enables negative edge capture. Match. When MATn = 1, a match of the PCA counter with this module's compare/capture register causes the CCFn bit in CCON to be set, flagging an interrupt. Toggle. When TOGn = 1, a match of the PCA counter with this module's compare/capture register causes the CEXn pin to toggle. Pulse Width Modulation Mode. PWMn = 1 enables the CEXn pin to be used as a pulse width modulated output. Enable CCF interrupt. Enables compare/capture flag CCFn in the CCON register to generate an interrupt. 7 ECOMn 6 CAPPn 5 CAPNn 4 MATn 3 TOGn 2 PWMn 1 ECCFn 0
NOTE: *User software should not write 1s to reserved bits. These bits may be used in future 8051 family products to invoke new features. In that case, the reset or inactive value of the new bit will be 0, and its active value will be 1. The value read from a reserved bit is indeterminate. SU00037
Figure 19. CCAPMn: PCA Modules Compare/Capture Registers - X X X X X X X X ECOMn 0 X X X 1 1 1 1 CAPPn 0 1 0 1 0 0 0 0 CAPNn 0 0 1 1 0 0 0 0 MATn 0 0 0 0 1 1 0 1 TOGn 0 0 0 0 0 1 0 X PWMn 0 0 0 0 0 0 1 0 ECCFn 0 X X X X X 0 X No operation 16-bit capture by a positive-edge trigger on CEXn 16-bit capture by a negative trigger on CEXn 16-bit capture by a transition on CEXn 16-bit Software Timer 16-bit High Speed Output 8-bit PWM Watchdog Timer MODULE FUNCTION
Figure 20. PCA Module Modes (CCAPMn Register) PCA Capture Mode To use one of the PCA modules in the capture mode either one or both of the CCAPM bits CAPN and CAPP for that module must be set. The external CEX input for the module (on port 1) is sampled for a transition. When a valid transition occurs the PCA hardware loads the value of the PCA counter registers (CH and CL) into the module's capture registers (CCAPnL and CCAPnH). If the CCFn bit for the module in the CCON SFR and the ECCFn bit in the CCAPMn SFR are set then an interrupt will be generated. Refer to Figure 21. 16-bit Software Timer Mode The PCA modules can be used as software timers by setting both the ECOM and MAT bits in the modules CCAPMn register. The PCA timer will be compared to the module's capture registers and when a match occurs an interrupt will occur if the CCFn (CCON SFR) and the ECCFn (CCAPMn SFR) bits for the module are both set (see Figure 22). High Speed Output Mode In this mode the CEX output (on port 1) associated with the PCA module will toggle each time a match occurs between the PCA counter and the module's capture registers. To activate this mode the TOG, MAT, and ECOM bits in the module's CCAPMn SFR must be set (see Figure 23). Pulse Width Modulator Mode All of the PCA modules can be used as PWM outputs. Figure 24 shows the PWM function. The frequency of the output depends on the source for the PCA timer. All of the modules will have the same frequency of output because they all share the PCA timer. The duty cycle of each module is independently variable using the module's capture register CCAPLn. When the value of the PCA CL SFR is less than the value in the module's CCAPLn SFR the output will be low, when it is equal to or greater than the output will be high. When CL overflows from FF to 00, CCAPLn is reloaded with the value in CCAPHn. the allows updating the PWM without glitches. The PWM and ECOM bits in the module's CCAPMn register must be set to enable the PWM mode.
1999 Oct 27
24
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
CF
CR
--
CCF4
CCF3
CCF2
CCF1
CCF0
CCON (D8H)
PCA INTERRUPT (TO CCFn) PCA TIMER/COUNTER CH CL
CEXn
CAPTURE
CCAPnH
CCAPnL
--
ECOMn 0
CAPPn
CAPNn
MATn 0
TOGn 0
PWMn 0
ECCFn
CCAPMn, n= 0 to 4 (DAH - DEH)
SU00749
Figure 21. PCA Capture Mode
CF WRITE TO CCAPnH RESET
CR
--
CCF4
CCF3
CCF2
CCF1
CCF0
CCON (D8H)
WRITE TO CCAPnL 0 1 ENABLE
CCAPnH
CCAPnL
PCA INTERRUPT (TO CCFn)
16-BIT COMPARATOR
MATCH
CH
CL
PCA TIMER/COUNTER
--
ECOMn
CAPPn 0
CAPNn 0
MATn
TOGn 0
PWMn 0
ECCFn
CCAPMn, n= 0 to 4 (DAH - DEH)
SU00750
Figure 22. PCA Compare Mode
1999 Oct 27
25
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
CF WRITE TO CCAPnH RESET CCAPnH
CR
--
CCF4
CCF3
CCF2
CCF1
CCF0
CCON (D8H)
WRITE TO CCAPnL 0 1 ENABLE
CCAPnL
PCA INTERRUPT (TO CCFn)
MATCH 16-BIT COMPARATOR
TOGGLE CH CL CEXn
PCA TIMER/COUNTER
--
ECOMn
CAPPn 0
CAPNn 0
MATn
TOGn 1
PWMn 0
ECCFn
CCAPMn, n: 0..4 (DAH - DEH)
SU00751
Figure 23. PCA High Speed Output Mode
CCAPnH
CCAPnL 0 CL < CCAPnL ENABLE 8-BIT COMPARATOR CL >= CCAPnL 1 OVERFLOW CL PCA TIMER/COUNTER CEXn
--
ECOMn
CAPPn 0
CAPNn 0
MATn 0
TOGn 0
PWMn
ECCFn 0
CCAPMn, n: 0..4 (DAH - DEH)
SU00752
Figure 24. PCA PWM Mode
1999 Oct 27
26
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
CIDL WRITE TO CCAP4H RESET
WDTE
--
--
--
CPS1
CPS0
ECF
CMOD (D9H)
WRITE TO CCAP4L 0 1 ENABLE
CCAP4H
CCAP4L
MODULE 4
MATCH 16-BIT COMPARATOR RESET
CH
CL
PCA TIMER/COUNTER
--
ECOMn
CAPPn 0
CAPNn 0
MATn 1
TOGn X
PWMn 0
ECCFn X
CCAPM4 (DEH)
SU00832
Figure 25. PCA Watchdog Timer m(Module 4 only) PCA Watchdog Timer An on-board watchdog timer is available with the PCA to improve the reliability of the system without increasing chip count. Watchdog timers are useful for systems that are susceptible to noise, power glitches, or electrostatic discharge. Module 4 is the only PCA module that can be programmed as a watchdog. However, this module can still be used for other modes if the watchdog is not needed. Figure 25 shows a diagram of how the watchdog works. The user pre-loads a 16-bit value in the compare registers. Just like the other compare modes, this 16-bit value is compared to the PCA timer value. If a match is allowed to occur, an internal reset will be generated. This will not cause the RST pin to be driven high. In order to hold off the reset, the user has three options: 1. periodically change the compare value so it will never match the PCA timer, 2. periodically change the PCA timer value so it will never match the compare values, or 3. disable the watchdog by clearing the WDTE bit before a match occurs and then re-enable it. The first two options are more reliable because the watchdog timer is never disabled as in option #3. If the program counter ever goes astray, a match will eventually occur and cause an internal reset. The second option is also not recommended if other PCA modules are being used. Remember, the PCA timer is the time base for all modules; changing the time base for other modules would not be a good idea. Thus, in most applications the first solution is the best option. Figure 26 shows the code for initializing the watchdog timer. Module 4 can be configured in either compare mode, and the WDTE bit in CMOD must also be set. The user's software then must periodically change (CCAP4H,CCAP4L) to keep a match from occurring with the PCA timer (CH,CL). This code is given in the WATCHDOG routine in Figure 26. This routine should not be part of an interrupt service routine, because if the program counter goes astray and gets stuck in an infinite loop, interrupts will still be serviced and the watchdog will keep getting reset. Thus, the purpose of the watchdog would be defeated. Instead, call this subroutine from the main program within 216 count of the PCA timer.
1999 Oct 27
27
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
INIT_WATCHDOG: MOV CCAPM4, #4CH MOV CCAP4L, #0FFH MOV CCAP4H, #0FFH
ORL CMOD, #40H
; ; ; ; ; ; ; ;
Module 4 in compare mode Write to low byte first Before PCA timer counts up to FFFF Hex, these compare values must be changed Set the WDTE bit to enable the watchdog timer without changing the other bits in CMOD
; ;******************************************************************** ; ; Main program goes here, but CALL WATCHDOG periodically. ; ;******************************************************************** ; WATCHDOG: CLR EA ; Hold off interrupts MOV CCAP4L, #00 ; Next compare value is within MOV CCAP4H, CH ; 255 counts of the current PCA SETB EA ; timer value RET Figure 26. PCA Watchdog Timer Initialization Code
1999 Oct 27
28
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
Expanded Data RAM Addressing
The 89C51RX+ has internal data memory that is mapped into four separate segments: the lower 128 bytes of RAM, upper 128 bytes of RAM, 128 bytes Special Function Register (SFR), and 256 bytes (768 for RD+) expanded RAM (ERAM). The four segments are: 1. The Lower 128 bytes of RAM (addresses 00H to 7FH) are directly and indirectly addressable. 2. The Upper 128 bytes of RAM (addresses 80H to FFH) are indirectly addressable only. 3. The Special Function Registers, SFRs, (addresses 80H to FFH) are directly addressable only. 4. The 256-bytes (768 for RD+) expanded RAM (ERAM, 00H - FFH) are indirectly accessed by move external instruction, MOVX, and with the EXTRAM bit cleared, see Figure 27. The Lower 128 bytes can be accessed by either direct or indirect addressing. The Upper 128 bytes can be accessed by indirect addressing only. The Upper 128 bytes occupy the same address space as the SFR. That means they have the same address, but are physically separate from SFR space. When an instruction accesses an internal location above address 7FH, the CPU knows whether the access is to the upper 128 bytes of data RAM or to SFR space by the addressing mode used in the instruction. Instructions that use direct addressing access SFR space. For example: MOV 0A0H,#data accesses the SFR at location 0A0H (which is P2). Instructions that use indirect addressing access the Upper 128 bytes of data RAM.
For example: MOV @R0,#data where R0 contains 0A0H, accesses the data byte at address 0A0H, rather than P2 (whose address is 0A0H). The ERAM can be accessed by indirect addressing, with EXTRAM bit cleared and MOVX instructions. This part of memory is physically located on-chip, logically occupies the first 256-bytes (768 for RD+) of external data memory. With EXTRAM = 0, the ERAM is indirectly addressed, using the MOVX instruction in combination with any of the registers R0, R1 of the selected bank or DPTR. An access to ERAM will not affect ports P0, P3.6 (WR#) and P3.7 (RD#). P2 SFR is output during external addressing. For example, with EXTRAM = 0, MOVX @R0,#data where R0 contains 0A0H, access the ERAM at address 0A0H rather than external memory. An access to external data memory locations higher than FFH (2FF for RD+) (i.e., 0100H to FFFFH) will be performed with the MOVX DPTR instructions in the same way as in the standard 80C51, so with P0 and P2 as data/address bus, and P3.6 and P3.7 as write and read timing signals. Refer to Figure 28. With EXTRAM = 1, MOVX @Ri and MOVX @DPTR will be similar to the standard 80C51. MOVX @ Ri will provide an 8-bit address multiplexed with data on Port 0 and any output port pins can be used to output higher order address bits. This is to provide the external paging capability. MOVX @DPTR will generate a 16-bit address. Port 2 outputs the high-order eight address bits (the contents of DPH) while Port 0 multiplexes the low-order eight address bits (DPL) with data. MOVX @Ri and MOVX @DPTR will generate either read or write signals on P3.6 (WR) and P3.7 (RD). The stack pointer (SP) may be located anywhere in the 256 bytes RAM (lower and upper RAM) internal data memory. The stack may not be located in the ERAM.
AUXR
Address = 8EH Not Bit Addressable -- Bit: 7 -- 6 -- 5 -- 4 -- 3 -- 2 EXTRAM 1 AO 0
Reset Value = xxxx xx00B
Symbol AO
Function Disable/Enable ALE AO Operating Mode 0 ALE is emitted at a constant rate of 1/6 the oscillator frequency. 1 ALE is active only during a MOVX or MOVC instruction. Internal/External RAM (00H - FFH) access using MOVX @Ri/@DPTR EXTRAM Operating Mode 0 Internal ERAM (00H-FFH) (00H-2FFH for RD+) access using MOVX @Ri/@DPTR 1 External data memory access. Not implemented, reserved for future use*.
EXTRAM
--
NOTE: *User software should not write 1s to reserved bits. These bits may be used in future 8051 family products to invoke new features. In that case, the reset or inactive value of the new bit will be 0, and its active value will be 1. The value read from a reserved bit is indeterminate.
SU00833A
Figure 27. AUXR: Auxiliary Register (RX+ only)
1999 Oct 27
29
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
2FF (89C51RD+)
FF
00
HARDWARE WATCHDOG TIMER (ONE-TIME ENABLED WITH RESET-OUT FOR 89C51RX+)
The WDT is intended as a recovery method in situations where the CPU may be subjected to software upset. The WDT consists of a 14-bit counter and the WatchDog Timer reset (WDTRST) SFR. The WDT is disabled at reset. To enable the WDT, user must write 01EH and 0E1H in sequence to the WDTRST, SFR location 0A6H. When WDT is enabled, it will increment every machine cycle while the oscillator is running and there is no way to disable the WDT except through reset (either hardware reset or WDT overflow reset). When WDT overflows, it will drive an output reset HIGH pulse at the RST-pin (see the note below).
Using the WDT
To enable the WDT, user must write 01EH and 0E1H in sequence to the WDTRST, SFR location 0A6H. When WDT is enabled, the user needs to service it by writing to 01EH and 0E1H to WDTRST to avoid WDT overflow. The 14-bit counter overflows when it reaches 16383 (3FFFH) and this will reset the device. When WDT is enabled, it will increment every machine cycle while the oscillator is running. This means the user must reset the WDT at least every 16383 machine cycles. To reset the WDT, the user must write 01EH and 0E1H to WDTRST. WDTRST is a write only register. The WDT counter cannot be read or written. When WDT overflows, it will generate an output RESET pulse at the reset pin (see note below). The RESET pulse duration is 98 x TOSC, where TOSC = 1/fOSC. To make the best use of the WDT, it should be serviced in those sections of code that will periodically be executed within the time required to prevent a WDT reset.
1999 Oct 27
EEEEE EEEEE EEEEE EEEEE EEEEE
ERAM 256 BYTES
FF
FF
FFFF
UPPER 128 BYTES INTERNAL RAM
SPECIAL FUNCTION REGISTER
EXTERNAL DATA MEMORY
80
80
LOWER 128 BYTES INTERNAL RAM 300 (89C51RD+) 00 00 0100 0000
SU00885
Figure 28. Internal and External Data Memory Address Space with EXTRAM = 0 NOTE: Applications which use the Watchdog Timer will need to include a series resistor (1 k, 20%) between the reset pin and ANY external components. Without this series resistor the Watchdog Timer will not function.
30
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
ABSOLUTE MAXIMUM RATINGS1, 2, 3
PARAMETER Operating temperature under bias Storage temperature range Voltage on EA/VPP pin to VSS Voltage on any other pin to VSS Maximum IOL per I/O pin RATING 0 to +70 or -40 to +85 -65 to +150 0 to +13.0 -0.5 to +6.5 15 UNIT C C V V mA
Power dissipation (based on package heat transfer limitations, not device power consumption) 1.5 W NOTES: 1. Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any conditions other than those described in the AC and DC Electrical Characteristics section of this specification is not implied. 2. This product includes circuitry specifically designed for the protection of its internal devices from the damaging effects of excessive static charge. Nonetheless, it is suggested that conventional precautions be taken to avoid applying greater than the rated maximum. 3. Parameters are valid over operating temperature range unless otherwise specified. All voltages are with respect to VSS unless otherwise noted.
1999 Oct 27
31
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
DC ELECTRICAL CHARACTERISTICS
Tamb = 0C to +70C or -40C to +85C; 5 V 10%; VSS = 0 V SYMBOL VIL VIH VIH1 VOL VOL1 VOH VOH1 IIL ITL ILI ICC Input low voltage Input high voltage (ports 0, 1, 2, 3, EA) Input high voltage, XTAL1, RST Output low voltage, ports 1, 2, 3 8 Output low voltage, port 0, ALE, PSEN 8, 7 Output high voltage, ports 1, 2, 3 3 Output high voltage (port 0 in external bus mode), ALE9, PSEN3 Logical 0 input current, ports 1, 2, 3 Logical 1-to-0 transition current, ports 1, 2, 36 Input leakage current, port 0 Power supply current (see Figure 36): Active mode (see Note 5) Idle mode (see Note 5) Power-down mode or clock stopped (see Figure 40 f conditions) for Fi diti ) Programming current Internal reset pull-down resistor Pin capacitance10 (except EA) VCC = 4.5 V IOL = 1.6 mA2 VCC = 4.5 V IOL = 3.2 mA2 VCC = 4.5 V IOH = -30 A VCC = 4.5 V IOH = -3.2 mA VIN = 0.4 V VIN = 2.0 V See Note 4 0.45 < VIN < VCC - 0.3 See Note 5 VCC - 0.7 VCC - 0.7 -1 -75 -650 10 PARAMETER TEST CONDITIONS 4.5 V < VCC < 5.5 V LIMITS MIN -0.5 0.2VCC+0.9 0.7VCC TYP1 UNIT MAX 0.2VCC-0.1 VCC+0.5 VCC+0.5 0.4 0.4 V V V V V V V A A A
Tamb = 0C to 70C Tamb = -40C to +85C 11.5 V v VPP v 12.5 V 40
20
100 125 50 225 15
A A mA k pF
IPP RRST CIO
NOTES: 1. Typical ratings are not guaranteed. The values listed are at room temperature, 5 V. 2. Capacitive loading on ports 0 and 2 may cause spurious noise to be superimposed on the VOLs of ALE and ports 1 and 3. The noise is due to external bus capacitance discharging into the port 0 and port 2 pins when these pins make 1-to-0 transitions during bus operations. In the worst cases (capacitive loading > 100 pF), the noise pulse on the ALE pin may exceed 0.8 V. In such cases, it may be desirable to qualify ALE with a Schmitt Trigger, or use an address latch with a Schmitt Trigger STROBE input. IOL can exceed these conditions provided that no single output sinks more than 5 mA and no more than two outputs exceed the test conditions. 3. Capacitive loading on ports 0 and 2 may cause the VOH on ALE and PSEN to momentarily fall below the VCC-0.7 specification when the address bits are stabilizing. 4. Pins of ports 1, 2 and 3 source a transition current when they are being externally driven from 1 to 0. The transition current reaches its maximum value when VIN is approximately 2 V. 5. See Figures 37 through 40 for ICC test conditions and Figure 36 for ICC vs Freq. Active mode: ICC(MAX) = (0.9 x FREQ. + 20)mA for all devices. Idle mode: ICC(MAX) = (0.37 x FREQ. +1.0)mA 6. This value applies to Tamb = 0C to +70C. 7. Load capacitance for port 0, ALE, and PSEN = 100 pF, load capacitance for all other outputs = 80 pF. 8. Under steady state (non-transient) conditions, IOL must be externally limited as follows: Maximum IOL per port pin: 15 mA (*NOTE: This is 85C specification.) 26 mA Maximum IOL per 8-bit port: Maximum total IOL for all outputs: 71 mA If IOL exceeds the test condition, VOL may exceed the related specification. Pins are not guaranteed to sink current greater than the listed test conditions. 9. ALE is tested to VOH1, except when ALE is off then VOH is the voltage specification. 10. Pin capacitance is characterized but not tested. Pin capacitance is less than 25 pF. Pin capacitance of ceramic package is less than 15 pF (except EA is 25 pF).
1999 Oct 27
32
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
AC ELECTRICAL CHARACTERISTICS
Tamb = 0C to +70C or -40C to +85C, VCC = 5 V 10%, VSS = 0 V1, 2, 3 VARIABLE CLOCK4 SYMBOL 1/tCLCL tLHLL tAVLL tLLAX tLLIV tLLPL tPLPH tPLIV tPXIX tPXIZ tAVIV tPLAZ Data Memory tRLRH tWLWH tRLDV tRHDX tRHDZ tLLDV tAVDV tLLWL tAVWL tQVWX tWHQX tQVWH tRLAZ tWHLH tCHCX tCLCX tCLCH tCHCL Shift Register tXLXL tQVXH tXHQX tXHDX 32 32 32 32 Serial port clock cycle time Output data setup to clock rising edge Output data hold after clock rising edge Input data hold after clock rising edge 12tCLCL 10tCLCL-133 2tCLCL-80 0 360 167 50 0 ns ns ns ns 30, 31 30, 31 30, 31 30, 31 30, 31 30, 31 30, 31 30, 31 30, 31 30, 31 30, 31 31 30, 31 30, 31 33 33 33 33 RD pulse width WR pulse width RD low to valid data in Data hold after RD Data float after RD ALE low to valid data in Address to valid data in ALE low to RD or WR low Address valid to WR low or RD low Data valid to WR transition Data hold after WR Data valid to WR high RD low to address float RD or WR high to ALE high High time Low time Rise time Fall time tCLCL-25 17 17 3tCLCL-50 4tCLCL-75 tCLCL-30 tCLCL-25 7tCLCL-130 0 tCLCL+25 tCLCL-tCLCX tCLCL-tCHCX 5 5 5 0 2tCLCL-28 8tCLCL-150 9tCLCL-165 3tCLCL+50 40 45 0 5 80 0 55 6tCLCL-100 6tCLCL-100 5tCLCL-90 0 32 90 105 140 82 82 60 ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns FIGURE 29 29 29 29 29 29 29 29 29 29 29 29 Oscillator frequency Speed versions: ALE pulse width Address valid to ALE low Address hold after ALE low ALE low to valid instruction in ALE low to PSEN low PSEN pulse width PSEN low to valid instruction in Input instruction hold after PSEN Input instruction float after PSEN Address to valid instruction in PSEN low to address float 0 tCLCL-25 5tCLCL-80 10 tCLCL-25 3tCLCL-45 3tCLCL-60 0 5 70 10 PARAMETER I;J;U (33 MHz) 2tCLCL-40 tCLCL-25 tCLCL-25 4tCLCL-65 5 45 30 MIN 3.5 MAX 33 3.5 21 5 5 55 33 33MHz CLOCK MIN MAX UNIT MHz ns ns ns ns ns ns ns ns ns ns ns
External Clock
tXHDV 32 Clock rising edge to input data valid 10tCLCL-133 167 ns NOTES: 1. Parameters are valid over operating temperature range unless otherwise specified. 2. Load capacitance for port 0, ALE, and PSEN = 100 pF, load capacitance for all other outputs = 80 pF. 3. Interfacing the microcontroller to devices with float times up to 45 ns is permitted. This limited bus contention will not cause damage to Port 0 drivers. 4. Parts are guaranteed to operate down to 0 Hz.
1999 Oct 27
33
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
EXPLANATION OF THE AC SYMBOLS
Each timing symbol has five characters. The first character is always `t' (= time). The other characters, depending on their positions, indicate the name of a signal or the logical status of that signal. The designations are: A - Address C - Clock D - Input data H - Logic level high I - Instruction (program memory contents) L - Logic level low, or ALE P - PSEN Q - Output data R - RD signal t - Time V - Valid W - WR signal X - No longer a valid logic level Z - Float Examples: tAVLL = Time for address valid to ALE low. tLLPL =Time for ALE low to PSEN low.
tLHLL
ALE
tAVLL
tLLPL
PSEN
tPLPH tLLIV tPLIV tPLAZ tPXIX
INSTR IN
tLLAX
tPXIZ
PORT 0
A0-A7
A0-A7
tAVIV
PORT 2 A0-A15 A8-A15
SU00006
Figure 29. External Program Memory Read Cycle
ALE
tWHLH
PSEN
tLLDV tLLWL
RD
tRLRH
tAVLL
PORT 0
tLLAX tRLAZ
A0-A7 FROM RI OR DPL
tRLDV tRHDX
DATA IN
tRHDZ
A0-A7 FROM PCL
INSTR IN
tAVWL tAVDV
PORT 2 P2.0-P2.7 OR A8-A15 FROM DPF A0-A15 FROM PCH
SU00025
Figure 30. External Data Memory Read Cycle
1999 Oct 27
34
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
ALE
tWHLH
PSEN
tLLWL
WR
tWLWH
tAVLL
PORT 0
tLLAX
tQVWX tQVWH
tWHQX
A0-A7 FROM RI OR DPL
DATA OUT
A0-A7 FROM PCL
INSTR IN
tAVWL
PORT 2
P2.0-P2.7 OR A8-A15 FROM DPF
A0-A15 FROM PCH
SU00026
Figure 31. External Data Memory Write Cycle
INSTRUCTION ALE
0
1
2
3
4
5
6
7
8
tXLXL
CLOCK
tQVXH
OUTPUT DATA 0 WRITE TO SBUF
tXHQX
1 2 3 4 5 6 7
tXHDV
INPUT DATA VALID CLEAR RI VALID
tXHDX
SET TI VALID VALID VALID VALID VALID VALID
SET RI
SU00027
Figure 32. Shift Register Mode Timing
VCC-0.5 0.45V
0.7VCC 0.2VCC-0.1
tCHCL
tCLCX tCLCL
tCHCX tCLCH
SU00009
Figure 33. External Clock Drive
1999 Oct 27
35
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
VCC-0.5
0.2VCC+0.9 VLOAD 0.2VCC-0.1
VLOAD+0.1V VLOAD-0.1V
TIMING REFERENCE POINTS
VOH-0.1V VOL+0.1V
0.45V
NOTE: AC inputs during testing are driven at VCC -0.5 for a logic `1' and 0.45V for a logic `0'. Timing measurements are made at VIH min for a logic `1' and VIL max for a logic `0'.
NOTE: For timing purposes, a port is no longer floating when a 100mV change from load voltage occurs, and begins to float when a 100mV change from the loaded VOH/VOL level occurs. IOH/IOL 20mA.
SU00717
SU00718
Figure 34. AC Testing Input/Output
Figure 35. Float Waveform
60
50
40
ICC (mA)
30
Icc ACTIVE MODE (TYP.) 20
10
Icc IDLE MODE (TYP.)
4
8
12
16
20
24
28
32
36
Frequency at XTAL1 (MHz)
SU01314
Figure 36. ICC vs. FREQ Valid only within frequency specifications of the device under test
1999 Oct 27
36
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
VCC ICC VCC VCC P0 EA (NC) CLOCK SIGNAL XTAL2 XTAL1 VSS (NC) CLOCK SIGNAL XTAL2 XTAL1 VSS VCC RST P0 EA VCC
VCC ICC
VCC
RST
SU00719
SU00720
Figure 37. ICC Test Condition, Active Mode All other pins are disconnected
Figure 38. ICC Test Condition, Idle Mode All other pins are disconnected
VCC-0.5 0.45V
0.7VCC 0.2VCC-0.1
tCHCL
tCLCX tCLCL
tCHCX tCLCH
SU00009
Figure 39. Clock Signal Waveform for ICC Tests in Active and Idle Modes tCLCH = tCHCL = 5 ns
VCC ICC VCC RST P0 EA (NC) XTAL2 XTAL1 VSS VCC
SU00016
Figure 40. ICC Test Condition, Power Down Mode All other pins are disconnected. VCC = 2 V to 5.5 V
1999 Oct 27
37
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
FLASH EPROM MEMORY GENERAL DESCRIPTION
The 89C51RX+ FLASH memory augments EPROM functionality with in-circuit electrical erasure and programming. The FLASH can be read and written as bytes. The Chip Erase operation will erase the entire program memory. The Block Erase function can erase any FLASH byte block. In-system programming and standard parallel programming are both available. On-chip erase and write timing generation contribute to a user friendly programming interface. The 89C51RX+ FLASH reliably stores memory contents even after 1000 erase and program cycles. The cell is designed to optimize the erase and programming mechanisms. In addition, the combination of advanced tunnel oxide processing and low internal electric fields for erase and programming operations produces reliable cycling. The 89C51RX+ uses a 12.0 V 0.5 V VPP supply to perform the Program/Erase algorithms.
CAPABILITIES OF THE PHILIPS 89C51 FLASH-BASED MICROCONTROLLERS FLASH organization (89C51RC+ and 89C51RD+)
The 89C51RD+ contains 64 k bytes of FLASH program memory. This memory is organized as 5 separate blocks. The first two blocks are 8 k bytes in size, filling the program memory space from address 0 through 3FFF hex. The final three blocks are 16 k bytes in size and occupy addresses from 4000 through FFFF hex. The 89C51RC+ contains 32 k bytes of FLASH program memory, which is organized as two blocks of 8k bytes, followed by one block of 16 k bytes. Figure 41 depicts the FLASH memory configurations.
FLASH Programming and Erasure
There are three methods of erasing or programming of the FLASH memory that may be used. First, the FLASH may be programmed or erased in the end-user application by calling low-level routines through a common entry point in the Boot ROM. The end-user application, though, must be executing code from a different block than the block that is being erased or programmed. Second, the on-chip ISP boot loader may be invoked. This ISP boot loader will, in turn, call low-level routines through the same common entry point in the Boot ROM that can be used by the end-user application. Third, the FLASH may be programmed or erased using the parallel method by using a commercially available EPROM programmer. The parallel programming method used by these devices is similar to that used by EPROM 87C51, but it is not identical, and the commercially available programmer will need to have support for these devices.
FEATURES
* FLASH EPROM internal program memory with Block Erase. * Internal 1 k byte fixed boot ROM, containing low-level in-system
programming routines and a default serial loader. The Boot ROM can be turned off to provide access to the full 64 k byte FLASH memory.
* Boot vector allows user provided FLASH loader code to reside
anywhere in the FLASH memory space. This configuration provides flexibility to the user.
* Default loader in Boot ROM allows programming via the serial port
without the need for a user provided loader.
Boot ROM
When the microcontroller programs its own FLASH memory, all of the low level details are handled by code that is permanently contained in a 1 k byte "Boot ROM" that is separate from the FLASH memory. A user program simply calls the common entry point with appropriate parameters in the Boot ROM to accomplish the desired operation. Boot ROM operations include things like: erase block, program byte, verify byte, program security lock bit, etc. The Boot ROM overlays the program memory space at the top of the address space from FC00 to FFFF hex, when it is enabled. The Boot ROM may be turned off so that the upper 1k bytes of FLASH program memory are accessible for execution.
* Up to 64 k byte external program memory if the internal program
memory is disabled (EA = 0).
* Programming and erase voltage 12 V 0.5 V. * Read/Programming/Erase:
- Byte-wise read (100 ns access time). - Byte Programming (20 s). - Typical erase times: Block Erase (8 k bytes or 16 k bytes) in 3 seconds. Full Erase (64 k bytes) in 3 seconds.
* Parallel programming with 87C51 compatible hardware interface
to programmer.
* In-circuit programming. * Programmable security for the code in the FLASH. * 1000 minimum erase/program cycles for each byte. * 10 year minimum data retention.
1999 Oct 27
38
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
FFFF BOOT ROM
FFFF FC00 BLOCK 4 16k BYTES (1k BYTES ON ALL PARTS)
C000
BLOCK 3 16k BYTES
PROGRAM ADDRESS
8000
89C51RD+
BLOCK 2 16k BYTES
4000 BLOCK 1 8k BYTES 2000 BLOCK 0 8k BYTES 0000
89C51RC+
SU01041
Figure 41. FLASH Memory Configurations
Power-On Reset Code Execution
The 89C51RX+ contains two special FLASH registers: the BOOT VECTOR and the STATUS BYTE. At the falling edge of reset, the 89C51RX+ examines the contents of the Status Byte. If the Status Byte is set to zero, power-up execution starts at location 0000H, which is the normal start address of the user's application code. When the Status Byte is set to a value other than zero, the contents of the Boot Vector is used as the high byte of the execution address and the low byte is set to 00H. The factory default setting is 0FCH, corresponds to the address 0FC00H for the factory masked-ROM ISP boot loader. A custom boot loader can be written with the Boot Vector set to the custom boot loader. NOTE: When erasing the Status Byte or Boot Vector, both bytes are erased at the same time. It is necessary to reprogram the Boot Vector after erasing and updating the Status Byte.
Hardware Activation of the Boot Loader
The boot loader can also be executed by holding PSEN LOW, EA greater than VIH (such as +12 V), and ALE HIGH (or not connected) at the falling edge of RESET. This is the same effect as having a non-zero status byte. This allows an application to be built that will normally execute the end user's code but can be manually forced into ISP operation. If the factory default setting for the Boot Vector (0FCH) is changed, it will no longer point to the ISP masked-ROM boot loader code. If this happens, the only way it is possible to change the contents of the Boot Vector is through the parallel programming method, provided that the end user application does not contain a customized loader that provides for erasing and reprogramming of the Boot Vector and Status Byte. After programming the FLASH, the status byte should be programmed to zero in order to allow execution of the user's application code beginning at address 0000H.
1999 Oct 27
39
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
VCC
VPP RST VCC TxD XTAL2 RxD
+12V
+5V TxD RxD VSS
XTAL1 VSS
SU01042
Figure 42. In-System Programming with a Minimum of Pins
In-System Programming (ISP)
The In-System Programming (ISP) is performed without removing the microcontroller from the system. The In-System Programming (ISP) facility consists of a series of internal hardware resources coupled with internal firmware to facilitate remote programming of the 89C51RX+ through the serial port. This firmware is provided by Philips and embedded within each 89C51RX+ device. The Philips In-System Programming (ISP) facility has made in-circuit programming in an embedded application possible with a minimum of additional expense in components and circuit board area. The ISP function uses five pins: TxD, RxD, VSS, VCC, and VPP (see Figure 42). Only a small connector needs to be available to interface your application to an external circuit in order to use this feature. The VPP supply should be adequately decoupled and provide a minimum 50mA. VPP is not allowed to exceed datasheet limits.
bytes. The "AAAA" string represents the address of the first byte in the record. If there are zero bytes in the record, this field is often set to 0000. The "RR" string indicates the record type. A record type of "00" is a data record. A record type of "01" indicates the end-of-file mark. In this application, additional record types will be added to indicate either commands or data for the ISP facility. The maximum number of data bytes in a record is limited to 16 (decimal). ISP commands are summarized in Table 8. As a record is received by the 89C51RX+, the information in the record is stored internally and a checksum calculation is performed. The operation indicated by the record type is not performed until the entire record has been received. Should an error occur in the checksum, the 89C51RX+ will send an "X" out the serial port indicating a checksum error. If the checksum calculation is found to match the checksum in the record, then the command will be executed. In most cases, successful reception of the record will be indicated by transmitting a "." character out the serial port (displaying the contents of the internal program memory is an exception). In the case of a Data Record (record type 00), an additional check is made. A "." character will NOT be sent unless the record checksum matched the calculated checksum and all of the bytes in the record were successfully programmed. For a data record, an "X" indicates that the checksum failed to match, and an "R" character indicates that one of the bytes did not properly program. It is necessary to send a type 02 record (specify oscillator frequency) to the 89C51RX+ before programming data. The ISP facility was designed to that specific crystal frequencies were not required in order to generate baud rates or time the programming pulses. The user thus needs to provide the 89C51RX+ with information required to generate the proper timing. Record type 02 is provided for this purpose. WinISP, a software utility to implement ISP programming with a PC, is available from Philips.
Using the In-System Programming (ISP)
The ISP feature allows for a wide range of baud rates to be used in your application, independent of the oscillator frequency. It is also adaptable to a wide range of oscillator frequencies. This is accomplished by measuring the bit-time of a single bit in a received character. This information is then used to program the baud rate in terms of timer counts based on the oscillator frequency. The ISP feature requires that an initial character (an uppercase U) be sent to the 89C51RX+ to establish the baud rate. The ISP firmware provides auto-echo of received characters. Once baud rate initialization has been performed, the ISP firmware will only accept Intel Hex-type records. Intel Hex records consist of ASCII characters used to represent hexadecimal values and are summarized below: :NNAAAARRDD..DDCC In the Intel Hex record, the "NN" represents the number of data bytes in the record. The 89C51RX+ will accept up to 16 (10H) data
1999 Oct 27
40
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
Table 8. Intel-Hex Records Used by In-System Programming
RECORD TYPE 00 COMMAND/DATA FUNCTION Program Data :nnaaaa00dd....ddcc Where: Nn = number of bytes (hex) in record Aaaa = memory address of first byte in record dd....dd = data bytes cc = checksum Example: :10008000AF5F67F0602703E0322CFA92007780C3FD End of File (EOF), no operation :xxxxxx01cc Where: xxxxxx = required field, but value is a "don't care" cc = checksum Example: :00000001FF Specify Oscillator Frequency :01xxxx02ddcc Where: xxxx = required field, but value is a "don't care" dd = integer oscillator frequency rounded down to nearest MHz cc = checksum Example: :0100000210ED (dd = 10h = 16, used for 16.0-16.9 MHz) Miscellaneous Write Functions :nnxxxx03ffssddcc Where: nn = number of bytes (hex) in record xxxx = required field, but value is a "don't care" 03 = Write Function ff = subfunction code ss = selection code dd = data input (as needed) cc = checksum Subfunction Code = 01 (Erase Blocks) ff = 01 ss = block code as shown below: block 0, 0k to 8k, 00H block 1, 8k to 16k, 20H block 2, 16k to 32k, 40H block 3, 32k to 48k, 80H block 4, 48k to 64k, C0H Example: :0200000301C03A erase block 4 Subfunction Code = 04 (Erase Boot Vector and Status Byte) ff = 04 ss = don't care Example: :020000030400F7 erase boot vector and status byte Subfunction Code = 05 (Program Security Bits) ff = 05 ss = 00 program security bit 1 (inhibit writing to Flash) 01 program security bit 2 (inhibit Flash verify) 02 program security bit 3 (disable external memory) Example: :020000030501F5 program security bit 2 Subfunction Code = 06 (Program Status Byte or Boot Vector) ff = 06 ss = 00 program status byte 01 program boot vector Example: :030000030601FCF7 program boot vector with 0FCH
01
02
03
1999 Oct 27
41
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
RECORD TYPE 04
COMMAND/DATA FUNCTION Display Device Data or Blank Check - Record type 04 causes the contents of the entire Flash array to be sent out the serial port in a formatted display. This display consists of an address and the contents of 16 bytes starting with that address. No display of the device contents will occur if security bit 2 has been programmed. Data to the serial port is initiated by the reception of any character and terminated by the reception of any character. General Format of Function 04 :05xxxx04sssseeeeffcc Where: 05 = number of bytes (hex) in record xxxx = required field, but value is a "don't care" 04 = "Display Device Data or Blank Check" function code ssss = starting address eeee = ending address ff = subfunction 00 = display data 01 = blank check cc = checksum Example: :0500000440004FFF0069 display 4000-4FFF
05
Miscellaneous Read Functions General Format of Function 05 :02xxxx05ffsscc Where: 02 = number of bytes (hex) in record xxxx = required field, but value is a "don't care" 05 = "Miscellaneous Read" function code ffss = subfunction and selection code 0000 = read signature byte - manufacturer id (15H) 0001 = read signature byte - device id # 1 (C2H) 0002 = read signature byte - device id # 2 0700 = read security bits 0701 = read status byte 0702 = read boot vector = checksum read signature byte - device id # 1
cc Example: :020000050001F8
1999 Oct 27
42
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
In Application Programming Method
Several In Application Programming (IAP) calls are available for use by an application program to permit selective erasing and programming of Flash sectors. All calls are made through a common interface, PGM_MTP. The programming functions are selected by setting up
the microcontroller's registers before making a call to PGM_MTP at FFF0H. The oscillator frequency is an integer number rounded down to the nearest megahertz. For example, set R0 to 11 for 11.0592 MHz. Results are returned in the registers. The IAP calls are shown in Table 9.
Table 9. IAP calls
IAP CALL PROGRAM DATA BYTE PARAMETER Input Parameters: R0 = osc freq (integer) R1 = 02h DPTR = address of byte to program ACC = byte to program Return Parameter ACC = 00 if pass, !00 if fail Input Parameters: R0 = osc freq (integer) R1 = 01h DPH = block code as shown below: block 0, 0k to 8k, 00H block 1, 8k to 16k, 20H block 2, 16k to 32k, 40H block 3, 32k to 48k, 80H block 4, 48k to 64k, C0H DPL = 00h Return Parameter none ERASE BOOT VECTOR Input Parameters: R0 = osc freq (integer) R1 = 04h DPH = 00h DPL = don't care Return Parameter none Input Parameters: R0 = osc freq (integer) R1 = 05h DPH = 00h DPL = 00h - security bit # 1 (inhibit writing to Flash) 01h - security bit # 2 (inhibit Flash verify) 02h - security bit # 3 (disable external memory) Return Parameter none Input Parameters: R0 = osc freq (integer) R1 = 06h DPH = 00h DPL = 00h - program status byte ACC = status byte Return Parameter ACC = status byte Input Parameters: R0 = osc freq (integer) R1 = 06h DPH = 00h DPL = 01h - program boot vector ACC = boot vector Return Parameter ACC = boot vector Input Parameters: R1 = 03h DPTR = address of byte to read Return Parameter ACC = value of byte read 43
ERASE BLOCK
PROGRAM SECURITY BIT
PROGRAM STATUS BYTE
PROGRAM BOOT VECTOR
READ DEVICE DATA
1999 Oct 27
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
IAP CALL READ MANUFACTURER ID Input Parameters: R0 = osc freq (integer) R1 = 00h DPH = 00h DPL = 00h (manufacturer ID) Return Parameter ACC = value of byte read Input Parameters: R0 = osc freq (integer) R1 = 00h DPH = 00h DPL = 01h (device ID # 1) Return Parameter ACC = value of byte read Input Parameters: R0 = osc freq (integer) R1 = 00h DPH = 00h DPL = 02h (device ID # 2) Return Parameter ACC = value of byte read Input Parameters: R0 = osc freq (integer) R1 = 07h DPH = 00h DPL = 00h (security bits) Return Parameter ACC = value of byte read Input Parameters: R0 = osc freq (integer) R1 = 07h DPH = 00h DPL = 01h (status byte) Return Parameter ACC = value of byte read Input Parameters: R0 = osc freq (integer) R1 = 07h DPH = 00h DPL = 02h (boot vector) Return Parameter ACC = value of byte read
PARAMETER
READ DEVICE ID # 1
READ DEVICE ID # 2
READ SECURITY BITS
READ STATUS BYTE
READ BOOT VECTOR
1999 Oct 27
44
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
Security
The security feature protects against software piracy and prevents the contents of the Flash from being read. The Security Lock bits are located in Flash. The P89C51RC+/P89C51RD+ has three programmable security lock bits that will provide different levels of protection for the on-chip code and data (see Table 10).
Table 10.
SECURITY LOCK BITS1 LB1 X 1 X X LB2 X X 1 X LB3 X X X 1 PROTECTION DESCRIPTION MOVC instructions executed from external program memory are disabled from fetching code bytes from internal memory. Block erase is disabled. Erase or programming of the status byte or boot vector is disabled. Verify of code memory is disabled. External execution is disabled.
NOTE: 1. Security bits are independent of each other. Full-chip erase may be performed regardless of the state of the security bits.
1999 Oct 27
45
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
DIP40: plastic dual in-line package; 40 leads (600 mil)
SOT129-1
1999 Oct 27
46
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
PLCC44: plastic leaded chip carrier; 44 leads
SOT187-2
1999 Oct 27
47
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
QFP44: plastic quad flat package; 44 leads
1999 Oct 27
48
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
NOTES
1999 Oct 27
49
Philips Semiconductors
Product specification
80C51 8-bit Flash microcontroller family 32K/64K ISP FLASH with 512-1K RAM
P89C51RC+/P89C51RD+
Data sheet status
Data sheet status Objective specification Preliminary specification Product specification Product status Development Qualification Definition [1] This data sheet contains the design target or goal specifications for product development. Specification may change in any manner without notice. This data sheet contains preliminary data, and supplementary data will be published at a later date. Philips Semiconductors reserves the right to make changes at any time without notice in order to improve design and supply the best possible product. This data sheet contains final specifications. Philips Semiconductors reserves the right to make changes at any time without notice in order to improve design and supply the best possible product.
Production
[1] Please consult the most recently issued datasheet before initiating or completing a design.
Definitions
Short-form specification -- The data in a short-form specification is extracted from a full data sheet with the same type number and title. For detailed information see the relevant data sheet or data handbook. Limiting values definition -- Limiting values given are in accordance with the Absolute Maximum Rating System (IEC 134). Stress above one or more of the limiting values may cause permanent damage to the device. These are stress ratings only and operation of the device at these or at any other conditions above those given in the Characteristics sections of the specification is not implied. Exposure to limiting values for extended periods may affect device reliability. Application information -- Applications that are described herein for any of these products are for illustrative purposes only. Philips Semiconductors make no representation or warranty that such applications will be suitable for the specified use without further testing or modification.
Disclaimers
Life support -- These products are not designed for use in life support appliances, devices or systems where malfunction of these products can reasonably be expected to result in personal injury. Philips Semiconductors customers using or selling these products for use in such applications do so at their own risk and agree to fully indemnify Philips Semiconductors for any damages resulting from such application. Right to make changes -- Philips Semiconductors reserves the right to make changes, without notice, in the products, including circuits, standard cells, and/or software, described or contained herein in order to improve design and/or performance. Philips Semiconductors assumes no responsibility or liability for the use of any of these products, conveys no license or title under any patent, copyright, or mask work right to these products, and makes no representations or warranties that these products are free from patent, copyright, or mask work right infringement, unless otherwise specified. Philips Semiconductors 811 East Arques Avenue P.O. Box 3409 Sunnyvale, California 94088-3409 Telephone 800-234-7381 (c) Copyright Philips Electronics North America Corporation 1999 All rights reserved. Printed in U.S.A. Date of release: 10-99 Document order number: 9397-750-06605
Philips Semiconductors
1999 Oct 27 50

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