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| 1 www.clare.com cpc2400e ds-cpc2400-r2 the cpc2400e is a 2400 baud embedded modem mod- ule intended for applications that require a data commu- nications link to the public switched telephone network (pstn). the cpc2400e is a complete module on a small 1.0?x 2.5?printed circuit board that can be socketed or soldered into the host system mother board. the module is fcc part 68 approved and includes a user trans- ferrable registration number. it also is a ul recognized component. the cpc2400e can be used in a variety of applications including set top box back channel commu- nications, vending machines, remote utility metering, remote data acquisition, plus a host of other applications. the cpc2400e supports a standard serial v.24 ttl interface to the dte equipment. vending/gaming machines set top box back channel direct broadcast satellite utility meters point of sale terminals remote diagnostics remote telemetry remote monitoring embedded applications ul/c-ul: 174201 fcc reg. # lvrphl-25931-md-e easy integration small footprint 1.00?x 2.50 full duplex 2400bps low power consumption v.24 dte interface single +5v supply operation supported protocols: v.22bis, v.23, v.22 ul recognized component fcc part 15b compliant fcc part 68 approved (user transferrable) applications features description approvals embedded modem module ordering information part # description cpc2400e 2400 baud embedded modem module pin configuration j1 v cc gnd -dtr -dcd -mute a1 n/c rxd txd j2 n/c tip n/c ring n/c block diagram v.22bis data pump controller daa parallel v.24 serial line interface dte tip ring audio out +5v gnd
www.clare.com cpc2400e rev. 2 electrical characteristics absolute maximum ratings are stress ratings. stresses in excess of these ratings can cause permanent damage to the device. functional operation of the device at these or any other conditions beyond those indicated in the operational sections of this data sheet is not implied. exposure of the device to the absolute maximum ratings for an extended period may degrade the device and effect its reliability. absolute maximum ratings (@ 25? c) 2 parameter conditions min typ max units dc electrical characteristics @ 25?c vcc supply voltage - 4.75 5.0 5.25 v vcc supply current - idle (sleep mode) vcc=5v - 5 10 ma vcc supply current - active vcc=5v - 70 100 ma line matching impedance vcc=5v - 600 - ? ringing voltage vcc=5v, f=20hz - 22 30 v rms ringer equivalence number (ren) vcc=5v - 0.6b - - telephone line loop current vcc=5v 20 - 120 ma dte dc characteristics @ 25?c input high voltage vih 2 - vcc+0.3 v input low voltage vil - 0 - 0.8 v input leakage current il gnd www.clare.com 4 cpc2400e rev. 2 functional description the cpc2400e is a small, full featured, 2400 baud module intended for embedded applications and is fully fcc part 68 approved. the cpc2400e includes a user transferable fcc registration number which the end product must display (see section for more details). the module consists of a data access arrangement (daa), v.22bis data pump, and a microcontroller on a 1.00 x 2.50 pcb. the cpc2400e connects to the telephone lines tip and ring leads and must be made through an approved rj-11 jack. the cpc2400e supports the industry stan- dard at command set (see at command set section for further details). the cpc2400e operates off a single +5v supply and supports low power modes of operation. when the device is not in use, it automatically enters sleep mode, reducing supply current to a minimum. an incoming ring signal from the phone lines powers up the device (wake- on ring). an evaluation board is available for testing the cpc2400e. this evaluation board includes an rs232 line driver, led status indicators and an amplified speak- er circuit. when used with the evaluation board, the cpc2400e also meets the fcc part 15b emissions test. contact clare for more information on the cpc2400e evaluation board. daa the daa portion of the cpc2400e has been designed to interface directly with the u.s. pstn as governed by the fcc. the daa includes the circuitry for hookswitch, ring detection, gyrator, surge protection and analog sig- nal coupling transformer. the daa circuitry provides up to 1000 v rms of longitudinal surge protection. for coun- tries using a pstn similar to the u.s. (canada, japan), the product using the cpc2400e must be submitted to a suitable test house for approval. consult clare for fur- ther information. fcc part 68: connecting to the pstn 1. general clare s cpc2400e complies with fcc part 68 rules which regulates equipment connected to the telephone network. the cpc2400e provides a user transferable part 68 registration which means that customers can use clare s registration number for the cpc2400e. customers who wish, can reregister the modem under their name. reregistration assigns the customer a unique registration number. no additional fcc part 68 submittal is required for equipment using clare s cpc2400e module. 2. repairs the fcc requires that clare makes all necessary repairs to the modem. if you are experiencing problems with the cpc2400e, contact clare at 1-800-272-5273 for further information. if repairs are necessary after the modem has been installed in your product and delivered to your customer, the modem must be returned to you where the cpc2400e can be removed and sent back to clare. 3. label instructions a label similar to the following should be made visible on the outside of the end user product. complies with part 68 of fcc rules registration number: lvrphl-25931-md-e ringer equivalence: 0.6b required connection: rj-11 4. design guidelines the following design guidelines should be followed to insure compatibility to fcc part 68 tests: 4.1. the cpc2400e, the rj-11 jack and the interface circuitry must be mounted on a pcb the should meet ul 94v-0 flammability standard. 4.2. tip and ring traces from the cpc2400e to the rj- 11 jack should be isolated by a minimum of 1.5mm (0.06in) to prevent breakdown. traces must have a min- imum width of 0.5mm (.02in). 4.3 insure that module is securely installed to the host system. vibration and drop tests will loosen compo- nents that are not securely mounted. one of two meth- ods for securing the module should be used: 4.3.1 soldered to the main pcb. this method is well suited for harsh environments where the end product may be subjected to shock and vibrationas in indus- trial environments (equipment monitoring, etc.). 4.3.2 socketed to the main pcb. this method is well suited for environments where the end product is not subjected to shock and vibrations as in consumer applications (set top boxes, etc.). 4.4. components used must be able to withstand tem- perature and humidity extremes per fcc part 68. cpc2400e www.clare.com 5 rev. 2 4.5. when connecting to the pstn, an fcc approved telephone jack must be used in the host system and must meet the mechanical requirements per fcc part 68.3 sub-part f. for rj-11 jacks, refer to fcc public notice #42269 for a list of approved vendors. 4.6. the supplied fcc registration number including ren must be visible on the outside of the end user product. see section 3. 5. exhibit j: user instructions instructions to our customers: the fcc part 68 rules require the following information (or equivalent) to be provided for the end user product. fcc requirements for consumer products this equipment complies with fcc rules, part 68. on the, [ ] front side [ ] bottom side [ ] back side [ ] top side of this equipment is a label that contains, among other information, the fcc registration number and ringer equivalence number (ren) for this equipment. if requested, provide this information to your telephone company. the (ren) is useful to determine the quantity of devices you may connect to your telephone line and still have all of those devices ring when your number is called. in most, but not all areas, the sum of the ren s of all devices should not exceed five (5.0). to be certain of the number of devices you may connect to your line, as determined by the ren, you should call your local tele- phone company to determine the maximum ren for your calling area. if this equipment causes harm to the telephone network, the telephone company may discontinue your service temporarily. if possible, they will notify you in advance. but if advance notice isn t practical, you will be notified as soon as possible. you will be advised of your right to file a complaint with the fcc. your telephone company may make changes in its facil- ities, equipment, operations, or procedures that could affect the proper operation of your equipment. if they do, you will be given advance notice so as to give you an opportunity to maintain uninterrupted service. if you experience trouble with this equipment, please contact (your company name) at (your company phone number) for warranty/repair information. the telephone company may ask that you disconnect this equipment from the network until the problem has been corrected or until you are sure that the equipment is not malfunc- tioning. this equipment may not be used on coin service pro- vided by the telephone company. connection to party lines is subject to state tariffs. fcc rules prohibit the use of non-hearing aid compati- ble telephones in the following locations or applications: (1) all public or semipublic coin-operated or credit card telephones. (2) elevators, highways, tunnels (automobile, subway, railroad or pedestrian) where a person with impaired hearing might be isolated in an emergency. (3) places where telephones are specifically installed to alert emergency authorities such as fire, police, or med- ical assistance personnel. (4) hospital rooms, residential health care facilities, con- valescent homes, and prisons. (5) workstations for the hearing impaired. (6) hotel, moel, apartment lobbies; in stores where tele- phones are used by patrons to order merchandise; in public transportation terminals where telephones are used to call taxis, or to reserve lodging or rental cars. (7) hotel and motel rooms. at least ten percent of the rooms must contain hearing aid compatible telephones; or jacks or plug-in hearing-aid compatible telephones which will be provided to hearing impaired customers upon request. www.clare.com 6 cpc2400e rev. 2 applications figure 1 is a schematic of the cpc2400e in a typical host system application. the host system communi- cates to the cpc2400e through a standard v.24 serial interface. refer to the pinout and definitions section for functional descriptions of the pins. the transmit and receive data is sent over the txd and rxd pins. the - dcd and -dtr pins are used for handshaking. the audio output pin, a1 is used for monitoring the analog data and can be amplified to drive a speaker. the - mute can be used to enable or disable the speaker. the ferrite beads fb1 and fb2 may be required to reduce emi emissions per fcc part 15. determining the value for the ferrite beads depends solely on the emissions generated by the end user product. figure 2 is a schematic of the cpc2400e in a stand- alone rs232c configuration. this circuit uses the linear technologies lt1181a rs232 line driver. note that the lt1181a line driver inverts the signals. both figures 1 and 2 are for reference purposes only. exact component values should be determined by the user. cpc2410e modem tip ring telephone line fb1 fb2 host system speaker audio amp rxd txd -dcd -dtr -mute a1 +5v vcc gnd cpc2400e modem tip ring telephone line fb1 fb2 rxd txd lt1181a 1 13 2 3 4 5 6 7 8 9 10 11 12 17 14 15 16 18 20 19 21 22 24 23 25 txd rxd 8 11 910 15 14 13 12 16 2 4 5 6 +5v 17 3 18 7 db25f rs232 driver +5v vcc gnd figure 1. cpc2400e system environment figure 2. stand alone modem with rs232c interface cpc2400e www.clare.com 7 rev. 2 command lines are typed to the modem from the termi- nal when the modem is in the idle or command state. the modem does not execute any of the commands in a command line until after the command line is ended by the end of line character www.clare.com 8 cpc2400e rev. 2 at command set command function and description a answer the a command makes the modem go off hook and respond to an incoming call. use this command after the modem has returned the ring result code. if the modems successfully complete the answering process they each return a connect result code and enter the on-line state. if no transmit carrier signal is received from the calling modem within the time specified in s-register s7, the modem hangs up, returns the no carrier result code, and enters the idle state. any commands following the answer command on the command line are ignored. this command is aborted if a key is pressed before the answer process is completed, or when dtr is off if some options in the &q or &d commands have been used. b communication the b command tells the modem which special telephone line modulation standards to use. the standard option modem can be configured to use: b0 use the itu-t modulation standards for all telephone line data rates. this includes v.22 for the 1200 bps telephone line data rate and v.21 for the 300 bps telephone line data rate. b1 not supported. &c data carrier &c determines how the modem s dcd signal relates to the carrier signal from the other detect options modem. this option takes effect only at the beginning of a telephone line connection. if &c is issued from the command state it will not have an immediate effect. &c0 during asynchronous operation (&q0 in effect) dcd is on at all times. during synchronous oper- ation (&q1) dcd reflects the state of the carrier signal from the other modem using s-registers s9 and s10. this is the default value in north america. &c1 reflects the state of the carrier signal from the other modem using s-registers s9 and s10. d dial the d command makes the modem dial a telephone call according to the digits and dial modifiers in the dial string following the command. any commands following the dial string on a command line are ignored unless the semicolon dial modifier is the last character in the dial string. if the modem was already off hook when the dial command was given, the modem dials immediately without trying to detect a dial tone. characters other than digits and dial modifiers in a dial string are ignored, but are counted as characters in the command line buffer. if line current sensing is enabled, and line current is detected before the modem is taken off-hook when the modem needs to dial, a no carrier result code is displayed and the modem enters the idle state. if the modem does not need to dial (i.e., atd with no dial string), the modem assumes the call was manual- ly established and attempts to make a connection. the d command is not valid when the modem is in the on-line state. see dial modifiers and modem result codes for more information. command function and description &d data terminal &d determines how the modem responds to the dtr signal from the terminal. the country ready options configuration may prevent the modem from detecting terminal dtr. in this case, the modem assumes dtr is always on. in north america, terminal dtr is normally detected. if dtr detection has been prevented, the modem will respond with an error result to this command. the response to changes in dtr also depends on the &q and &d commands. this table defines what happens when dtr goes off for all possible combinations of the &d and &q commands. to see what happens when dtr goes on refer to the &q command. the default value is &d0 in north america: &d0 &d1 &d2 d3 &q0 none b c d &q1 a b c d a the modem hangs up the telephone line and issues an ok result code. b if in the on-line state, the modem goes into the command state and issues an ok result code. c the modem hangs up the telephone line and issues an ok result code. auto-answer is disabled as long as dtr stays off. d the modem resets. e command mode e tells the modem whether or not to echo characters sent from the terminal when the modem is character echo accepting at commands. e0 does not echo characters sent from the terminal. e1 echo characters sent from the terminal. this is the default value in north america. %e automatic retrain the %e command controls whether the modem will initiate retrain with the other modem during options a telephone line connection during operation in data modes supporting retrain. the modem always responds to a retrain operation initiated by the remote modem. the modem can be forced to initiate a retrain by the on-line (o1) command. %e0 do not initiate a retrain. %e1 initiate a retrain if the datapump indicates one is required. &f recall factory &f changes these at command options and s-registers to their default values. the default profile values may be changed for use in different countries. the values for north america are: s-registers s0=0 s1=0 s2=43 s3=13 s4=10 s5=8 s6=2 s7=30 s8=2 s9=6 s10=14 s11=95 s12=50 s17=10 s25=5 s28=0 s29=25 s37=0 commands b1 e1 m1 p q0 v1 x4 &c0 &d0 &g0 &p0 &q0 %e1 &g guard tone options &g tells the modem which guard tone to transmit when the modem is transmitting the high band (i.e., answer handshake and answer mode). &g0 no guard tone. this is the default value in north america. &g1 550 hz guard tone (v.22 and v.22bis only) &g2 1800 hz guard tone (v.22 and v.22bis only) cpc2400e www.clare.com 9 rev. 2 at command set www.clare.com 10 cpc2400e rev. 2 command function and description h hook h0 hang up the telephone line. h1 go off hook without answering a telephone call. this may be disabled in countries prohibiting its use. &ht ptt test command the &ht command causes the modem to transmit tones for ptt testing. the test tone is generated until a character is typed on the modem s terminal. the country configuration may disable this com- mand. the modem returns an error result if this command is issued. &ht0-9 emmf tone for digit n where the command was &htn. &ht10 emmf tone? &ht11 emmf tone ? &ht12 emmf tone ? &ht13 emmf tone ? &ht14 emmf tone ? &ht15 emmf tone ? &ht16 v.21 channel 1 mark &ht17 v.21 channel 2 marks &ht18 v.23 1200bps marks &ht19 v.23 75bps marks &ht20 v.21 channel 1 spaces &ht21 v.21 channel 2 spaces &ht22 v.23 1200bps spaces &ht23 v.23 75bps spaces &ht24 v.22 originate mode &ht25 v.22 answer mode &ht26 v.22bis originate mode &ht27 v.22bis answer mode &ht28 v.25 calling tone &ht29 550hz guard tone &ht30 1800hz guard tone &ht31 silence i identification the i command asks the modem for information that can be used to determine the modem s compati- bility with other software and to ensure the modem is operating properly. i0 display product code. the modem reports its product code to the terminal. the modem pro- duces information text dependent upon its features and capabilities. i1 display rom checksum. the modem reports the value of its rom checksum. the decimal num- ber displayed is the eight bit sum (from 0 to 255) of all the bytes in rom. i2 test the rom checksum. the modem checks its rom to ensure it is correct. the modem reports a result code indicating whether the rom is ok or in error. i3 display software versions. the modem reports the modem controller and data pump software versions, and the modem controller software release date, to the terminal. i4 display modem identification. the modem reports a configurable identification message to the terminal. at command set command function and description m speaker on/off the country configuration may disable the speaker. if so, this command will return an options error result. m0 speaker always off. m1 speaker on until carrier detected. this is the default value in north america. m2 speaker always on; stays on after carrier is detected. m3 speaker off as digits are dialed, but on during ringback and on until carrier signal is detected. o return to on-line this command returns the modem to the on-line mode. it is frequently used after th escape character mode sequence (+++) to resume communication with the remote modem. if handshaking is started, the modem uses originate or answer mode handshaking depending upon whether the modem originated or answered the telephone call. o0 return the modem to the on-line state from the command state during a telephone line connection. the modem starts handshaking if there was no telephone line connection but the modem was off hook. o1 return the modem to the on-line state and retrain its data pump during a telephone line connection. the modem starts handshaking if there was no telephone line connection but the modem was off hook. &p pulse dial make/ sets cadence of pulse dial. the country configuration may disable this command, forcing particular break ratios pulse dialing parameters. in this event, the modem returns an error result if this command is issued. &p0 39%/61% make/break ratio and 10 pulses per second when pulse dialing. this is the default value. &p1 33%/67% make/break ratio and 10 pulses per second when pulse dialing. &p2 39%/61% make/break ratio and 20 pulses per second when pulse dialing. q &p3 33%/67% make/break ratio and 20 pulses per second when pulse dialing q result code this command allows the user to either display result codes or to not display result codes. display options q0 result codes will be displayed. this is the default value for north america. q1 result codes will not be displayed. sn set the current this command sets the current s-register to the value ??selected by the user. for example, ats7 will s-register to n set the current s-register to s7. default value is 0. sn addresses a particular s-register number so future commands like ? and = will read of write the s-register. modem reset and the &f command select s0 as the default s-register. ? read an s-register this command displays the value of the last s-register named in the sn command. =x write an s-register this command writes the value x to the last s-register named in the sn command. the range of valid values for x depends upon which s-register is being written. 0 is assumed if no value is given for x. t tone dialing selects the tone method of dialing. v result code format this command changes the format in which result codes are displayed. v0 all result codes will be displayed as numbers. v1 all result codes will be displayed as words (verbose form). this is the default value for north america. cpc2400e www.clare.com 11 rev. 2 at command set command function and description x call progress the x command controls whether or not a busy signal or dial tone should be detected when dialing. the x command also limits the result codes the modem may return when dialing. the operation of the x command is configurable for operation in different countries. x0 neither busy signal nor dial tone are detected. when a telephone line connection is made the result code does not indicate the telephone line data rate. x1 neither busy signal nor dial tone are detected. when a telephone line connection is made the result code indicates the telephone line data rate. x2 busy signal is not detected. dial tone is detected. when a telephone line connection is made the result code indicates the telephone line data rate. x3 busy signal is detected. dial tone is not detected. when a telephone line connection is made the result code indicates the telephone line data rate. x4 both busy signal and dial tone are detected. when a telephone line connection is made the result code indicates the telephone line data rate. this is the default value in north america. the @ and w dial modifiers are not affected by the x command. the @ dial modifier may return the result codes 8 (no answer) or 7 (busy) each time it appears in the dial string. the w dial modifier may return the result codes 6 (no dialtone) or 7 (busy) each time it appears in the dial string. www.clare.com 12 cpc2400e rev. 2 at command set cpc2400e www.clare.com 13 rev. 2 dial modifiers perform special functions within a dial command. for example, atdt9w1552368!@#71234; www.clare.com 14 cpc2400e rev. 2 modem s-registers the value of an s-register is modified by atsn =x, where n is the register number and x is the value to be stored in that particular register. each s-register has three values that may be configured for different coun- tries: a default value, an upper limit and a lower limit. the values shown in this manual are for north america. register range units description s0 0 - 255 rings set number of rings to auto-answer. the country configuration may disable the modem s ability to detect a telephone line ring signal. in this case the modem will never automatically answer the telephone regardless of the s0 setting. default = 0 (auto-answer disabled) s1 0 - 255 rings returns the number of times the phone rings. default = 0 s2 0 - 255 ascii set escape sequence character. setting s2 to a value greater than 127 disables the character escape sequence, preventing the modem from returning to command state when in the on-line state. default = 43 s3 0 - 127 ascii set the end of line character. default = 13 s4 0 - 127 ascii set the line feed character. default = 10 s5 0 - 127 ascii set the backspace character. default = 8 s6 2 - 255 seconds delay to wait before performing a blind dial. default = 2 seconds s7 1 - 255 seconds delay to wait for carrier after dialing. default = 30 seconds s8 0 - 255 seconds delay to wait when a comma dial modifier is processed. default = 2 sec. s9 1 - 255 1/10th sec time carrier must be present before being recognized. default = 0.6 sec. s10 1 - 255 1/10th sec delay between lost carrier and hang up. setting s-register s10 to 255 makes the modem never hang up the telephone line because of a loss of carrier. default = 14 tenths of a second s11 50 - 255 msec multi-frequency tone duration. default = 95 milliseconds s12 0 - 255 1/50th sec escape prompt delay time. this is the prompt delay time for escape sequences from the on-line state to the command state. default = 50 fiftieths of a second s13 reserved reserved reserved s14 reserved reserved reserved s15 reserved reserved reserved s16 reserved reserved reserved s17 -6 to -43 - dbm set transmit level. default = -10 dbm s18 reserved reserved reserved s19 reserved reserved reserved s20 reserved reserved reserved cpc2400e www.clare.com 15 rev. 2 register range units description s21 reserved reserved reserved s22 reserved reserved reserved s23 reserved reserved reserved s24 reserved reserved reserved s25 0 - 255 seconds or during synchronous operation with the &q1 command in effect, s-register s25 is 1/100 sec. the number of seconds after a telephone line connection is made before the modem examines dtr. this allows sufficient time to disconnect the modem from an asyn- chronous terminal and attach it to a synchronous terminal. in the on-line or command state during any mode of operation, changes in dtr for less than s25 hundredths of a second are ignored. s26 reserved reserved reserved s27 reserved reserved reserved s28 0 - 255 minutes terminal inactivity timeout. hangs up the modem after s28 minutes if no characters are received from the modem s terminal. default = 0 s29 0 - 255 1/50th sec hook flash on-hook time. the amount of time in 20 millisecond units the modem will leave the telephone on-hook while performing a hook-flash according to the ? dial string modifier. default = 25 fiftieths of a second. s37 0 - 6 code set highest line rate - determines the highest telephone line data rate the modem will use when connecting with a remote modem. see ?etting the highest line rate?section below. default = 0. s37 value carrier data rate 0 the data rate of the last at command 4 reserved 5 v.22, bell 212a 1200 bps. see the b command 6 v.22bis 2400 bps setting the highest line rate modem s-registers the connect rate can be selected by s-register s37. the following connect rates are supported. www.clare.com 16 cpc2400e rev. 2 a result code is a line of text or a number the modem sends to the terminal to indicate the result of a com- mand execution. some connect result codes indi- cate the telephone line data rate. the following table provides a list of the available result codes. modem result codes number word result code description 0 ok command line executed without errors 1 connect the modem is in the on-line state, ready to transfer data. 2 ring the modem has detected a ring signal on the telephone line. the country configuration may disable the modem s ability to detect a telephone line ring signal. 3 no carrier no carrier signal was detected when answering or placing a telephone call, or carrier was lost during a call. the modem also returns this response message when the tele phone line connection is broken for any reason. 4 error an invalid command was issued, or there was an error at any place in the command line. 5 connect 1200 the modem is in the on-line state, ready to transfer data. 6 no dialtone no dial tone was detected when the modem took the telephone line off hook. 7 busy the modem detected a busy signal on the telephone line. 8 no answer not enough silence was detected when the @ dial modifier was used. 10 connect 2400 the modem is in the on-line state, ready to transfer data. the telephone line data rate is 2400bps. 16 connect 1200/75 the modem is in the on-line state, ready to transfer data. this modem transmits at 1200 bps and receives at 75 bps. 17 connect 75/1200 the modem is in the on-line state, ready to transfer data. this modemtransmits at 75 bps and receives at 1200 bps. 20 blacklisted the modem will not allow any number to be dialed until after the modem is reset. 21 delayed the modem will not allow any number to be dialed now, but will allow dialing at some future time. cpc2400e www.clare.com 17 rev. 2 an escape sequence is one or more particular characters sent from the terminal to the modem during the on-line state. this is done to switch the modem to the command state so modem commands may be entered during a telephone line connection. the escape sequence char- acters are typically sent to the other modems as data. an escape sequence should not occur accidentally dur- ing an exchange of data between two modems. unfortunately, it is impossible to guarantee any escape sequence will never occur naturally since there are no restrictions on the data or timing between characters sent between two modems during the on-line state. the only method of switching form the on-line state to the command state that does not ever occur naturally during an exchange of data is the data terminal ready signal (the &d1 command). the terminal has complete control of this signal and it is not part of the data exchanged between the modems. the hayes escape sequence was adopted by many modem manufacturers and communication programs before hayes was granted a patent for the escape sequence guard times. now the unpatented time independent escape sequence (ties) has gained pop- ularity with many modem manufacturers. ties escape sequence ties stands for time independent escape sequence. ties was developed by a number of modem manufac- turers in response to hayes enforcing patent rights for their escape sequence guard time patent. the time independent escape sequence is a sequence of 3 escape characters (+ characters by default). once these characters have been recognized, the modem enters the command state without sending a confirming result code to the terminal and the modem starts a prompt delay timer. then: a. if one of the recognized at commands is received before the timer expires, the timer is stopped, the com- mand is executed and its result code is sent to the ter- minal. b. if any other data is received while the timer is running, the timer is stopped, the modem returns to the on-line state and the received data is sent to the other modem. c. if the timer expires, a confirming result code is sent to the terminal, indicating the modem is in the command state. the escape character can be changed through escape sequences s-register s2. the prompt delay timer can be changed (in 1/50 second increments) through s-register s12 (see s-registers section). after handshaking, the modem determines if a tele- phone line connection exists by detecting the carrier sig- nal from the other modem. if the carrier is not detected for a long enough period of time, the modem assumes the telephone line connection with the other modem has been broken. the modem uses s-register s9 to deter- mine how long a carrier must be present before it is detected. the modem uses s-register s10 to deter- mine how long a carrier may not be detected before the telephone line is hung up. carrier detection clare, inc. makes no representations or warranties with respect to the accuracy or completeness of the contents of this publica tion and reserves the right to make changes to specifications and product descriptions at any time without notice. neither circuit patent licenses nor indemnity are expressed or implied. except as set forth in cl are s standard terms and conditions of sale, clare, inc. assumes no liability whatsoever, and disclaims any express or implied warranty, relating to its products including, but not limited to, the implied warranty of merc hantability, fitness for a particular purpose, or infringement of any intellectual property right. the products described in this document are not designed, intended, authorized or warranted for use as components in systems intended for surgical implant into the body, or in other applications intended to sup- port or sustain life, or where malfunction of clare s product may result in direct physical harm, injury, or death to a person or severe property or environmental damage. clare, inc. reserves the right to discontinue or make changes to its products at any time without notice. specification: ds - cp c 24 00 e -r2.0 ?copyright 2002, clare, inc. all rights reserved. printed in usa. 6/25/02 for additional information please visit our website at: www.clare.com |
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