MICROCOM, INC.
DESKPORTE 28.8S
Modem Type |
Data (synchronous/asynchronous)/Fax |
Maximum Data Rate |
28.8Kbps |
Maximum Fax Rate |
Unidentified |
Data Bus |
External |
Fax Class |
Unidentified |
Data Modulation Protocol |
Bell 103A/212A ITU-T V.21, V.22, V.22bis, V.23, V.32, V.32bis, V.34 Rockwell V.FC |
Fax Modulation Protocol |
Unidentified |
Error Correction/Compression |
MNP5, MNP10, V.42, V.42bis |
CONNECTIONS | |||
Purpose |
Location |
Purpose |
Location |
Line out |
CN1 |
DC power |
CN4 |
Line in |
CN2 |
Power switch |
SW1 |
RS-232/422 |
CN3 |
DIAGNOSTIC LED(S) | |||
LED |
Color |
Status |
Condition |
AA |
Red |
On |
Auto-answer enabled |
AA |
Red |
Off |
Auto-answer disabled |
RD |
Red |
On |
Modem is receiving data |
RD |
Red |
Off |
Modem is not receiving data |
SD |
Red |
On |
Modem is transmitting data |
SD |
Red |
Off |
Modem is not transmitting data |
CD |
Red |
On |
Carrier signal detected |
CD |
Red |
Off |
Carrier signal not detected |
OH |
Red |
On |
Modem is off-hook |
OH |
Red |
Off |
Modem is on-hook |
TR |
Red |
On |
DTR signal is high |
TR |
Red |
Off |
DTR signal is low |
TM |
Red |
On |
Test mode enabled |
TM |
Red |
Off |
Test mode disabled |
TM |
Red |
Slow blink |
RAM test failed |
TM |
Red |
Medium blink |
ROM test failed |
TM |
Red |
Fast blink |
MDP(Data Pump) test failed |
Proprietary AT Command Set
AUTO-RETRAIN - FALLBACK/FALLFORWARD | |
Type: |
Configuration |
Format: |
AT [cmds] %En [cmds] |
Description: |
Controls auto-retrain mode and fallback/fall forward |
Command |
Function |
%E0 |
Auto-retrain disabled |
%E1 |
Auto-retrain enabled |
» %E2 |
Fallback/fall forward enabled |
%E3 |
Auto-retrain enabled, modem will hang up if EQM reaches hang up threshold |
BIT-MAPPED REGISTER S14 | |||
Format |
AT [cmds] S14=n [cmds] | ||
Default: |
138 | ||
Range: |
0-174 | ||
Unit: |
Bit-mapped | ||
Description: |
Controls echo, result codes, result code display, dial mode, and answer/originate mode | ||
Bit |
Value |
Function | |
0 |
0 |
Not used | |
1 |
0 » 1 |
Command echo disabled Command echo enabled | |
2 |
» 0
1 |
Result codes enabled Result codes disabled | |
3 |
0 » 1 |
Display result codes in numeric format Display result codes in verbose format | |
4 |
0 |
Not used | |
5 |
» 0
1 |
Tone dial enabled Pulse dial enabled | |
6 |
0 |
Not used | |
7 |
0 » 1 |
Answer mode enabled Originate mode enabled |
BIT-MAPPED REGISTER S21 | |||
Format |
AT [cmds] S21=n [cmds] | ||
Default: |
0 | ||
Range: |
0-248 | ||
Unit: |
Bit-mapped | ||
Description: |
Selects low DTR action, DCD signal, DSR signal, and the Long Space Disconnect function | ||
Bit |
Value |
Function | |
2 - 0 |
0 |
Not used | |
4, 3 |
» 00
01 10 11 |
DTR signal ignored Modem goes to command mode on low DTR Modem disconnects on low DTR Auto-Answer is disabled Modem is initialized on low DTR | |
5 |
» 0
1 |
DCD forced high DCD normal | |
6 |
» 0
1 |
DSR forced high DSR normal | |
7 |
» 0
1 |
Long Space Disconnect function disabled Long Space Disconnect function enabled |
BIT-MAPPED REGISTER S22 | |||
Format |
AT [cmds] S22=n [cmds] | ||
Default: |
117 | ||
Range: |
0-127 | ||
Unit: |
Bit-mapped | ||
Description: |
Controls speaker volume and controls, and limits results codes | ||
Bit |
Value |
Function | |
1, 0 |
00 » 01 10 11 |
Off volume Low level volume Medium level volume High level volume | |
3, 2 |
00 » 01 10 11 |
Speaker off Speaker off on carrier Speaker always on Speaker on during handshake | |
6, 5, 4 |
000 100 101 110 » 111 |
Basic result codes only enabled Basic and connection speed result codes enabled Basic and connection speed result codes and dialtone detection enabled All result codes except dialtone detection enabled All result codes enabled |
BIT-MAPPED REGISTER S23 | |||
Format |
AT [cmds] S23=n [cmds] | ||
Default: |
55 | ||
Range: |
0-189 | ||
Unit: |
Bit-mapped | ||
Description: |
Grants/denies remote digital loopback, controls DTE rate and parity, and sets guard tone | ||
Bit |
Value |
Function | |
0 |
0 » 1 |
Remote digital loopback denied Remote digital loopback allowed | |
3, 2, 1 |
000 001 010 » 011 100 101 110 |
Sets serial port speed to 0-300bps Sets serial port speed to 600bps Sets serial port speed to 1200bps Sets serial port speed to 2400bps Sets serial port speed to 4800bps Sets serial port speed to 9600bps Sets serial port speed to 19200bps | |
5,4 |
00 01 10 » 11 |
Parity even Not used Parity odd No Parity | |
7, 6 |
» 00
01 10 |
Guard tone disabled Guard tone disabled Guard tone 1800Hz enabled |
BIT-MAPPED REGISTER S27 | |||
Format |
AT [cmds] S27=n [cmds] | ||
Default: |
73 | ||
Range: |
0-73 | ||
Unit: |
Bit-mapped | ||
Description: |
Selects sync/async mode and ITU-T/Bell modes | ||
Bit |
Value |
Function | |
3, 1, 0 |
000 » 101 |
Asynchronous mode, serial port speed follows connect speed Error correction mode | |
5, 4, 2 |
0 |
Not used | |
6 |
0 » 1 |
CCITT mode Bell mode |
BIT-MAPPED REGISTER S28 | |||
Format |
AT [cmds] S28=n [cmds] | ||
Default: |
0 | ||
Range: |
0-128 | ||
Unit: |
Bit-mapped | ||
Description: |
Controls pulse dialing and MNP10 link negotiation | ||
Bit |
Value |
Function | |
2 - 0 |
0 |
Not used | |
4, 3 | » 00 |
39ms make/61ms break at 10pps | |
5 |
0 |
Not used | |
7, 6 |
» 00
01 10 |
Link will be negotiated at highest possible speed Link will be negotiated at 1200bps Link will be negotiated at 4800bps |
BIT-MAPPED REGISTER S31 | |||
Format |
AT [cmds] S31=n [cmds] | ||
Default: |
2 | ||
Range: |
0-10 | ||
Unit: |
Bit-mapped | ||
Description: |
Controls auto-baud function and result codes | ||
Bit |
Value |
Function | |
0 |
0 |
Not used | |
1 |
0 » 1 |
Auto-baud disabled Auto-baud enabled | |
3, 2 |
» 00
01 10 |
DTE speed displayed in result codes Extended result codes enabled; DCE speed displayed in result codes. DCE speed displayed in result codes |
BIT-MAPPED REGISTER S40 | |||
Format |
AT [cmds] S40=n [cmds] | ||
Default: |
105 | ||
Range: |
0-239 | ||
Unit: |
Bit-mapped | ||
Description: |
Controls power level and break handling; selects MNP extended services, link negotiation, and block size | ||
Bit |
Value |
Function | |
1, 0 |
00 » 0110 |
MNP10 disabled MNP10 enabled MNP10 enabled on originate mode only | |
0 |
0 » 1 |
MNP10 disabled MNP10 enabled | |
1 |
0 » 1 |
MNP10 at 2400 and 1200bps disabled MNP10 at 2400 and 1200bps enabled | |
2 |
» 0
1 |
Power level adjustment disabled Power level adjustment enabled | |
5, 4, 3 |
000 001 010 011 100 » 101 |
\K0 \K1 \K2 \K3 \K4 \K5 | |
7, 6 |
00 » 0110 11 |
MNP block size is 64 characters MNP block size is 128 characters MNP block size is 192 characters MNP block size is 256 characters |
BIT-MAPPED REGISTER S41 | |||
Format |
AT [cmds] S41=n [cmds] | ||
Default: |
195 | ||
Range: |
0-223 | ||
Unit: |
Bit-mapped | ||
Description: |
Selects compression, auto-retrain, flow control, MNP mode, and fallback-V.22/22bbis | ||
Bit |
Value |
Function | |
1 - 0 |
00 01 10 » 11 |
Data compression disabled MNP5 enabled V.42bis enabled MNP5 and V.42bis enabled | |
6, 2 |
00 01 » 1011 |
Auto-retrain disabled Auto-retrain enabled Fallback/fall forward enabled Auto-retrain enabled, modem will hang up if EQM reaches hang up threshold | |
3 |
» 0
1 |
Flow control disabled Flow control enabled | |
4 |
» 0
1 |
Stream mode for MNP Block mode for MNP | |
5 |
0 |
Not used | |
7 |
0 » 1 |
MNP10 at 2400 and 1200bps disabled MNP10 at 2400 and 1200bps enabled |
BREAK SEND | |
Type: |
Configuration |
Format: |
AT [cmds] \Bn [cmds] |
Default: |
3 |
Range: |
1-9 |
Unit: |
.1 second |
Description: |
Sends break to modem |
BREAK TYPE | ||||
Type: |
Configuration | |||
Format: |
AT [cmds] \Kn [cmds] | |||
Description: |
Configures action of break signal | |||
Command |
Break from DTE Reliable/Normal mode |
Break from DTE Direct mode |
Break from remote modem | |
\K0 |
Enter command mode, do not send break to remote modem |
Send break to remote modem immediately, then enter command mode |
Buffers cleared and break sent to DTE | |
\K1 |
Buffers cleared and break sent to remote modem |
Send break to remote modem immediately, then enter command mode |
Buffers cleared and break sent to DTE | |
\K2 |
Enter command mode, do not send break to remote modem |
Send break to remote modem immediately |
Send break to DTE immediately | |
\K3 |
Send break to remote modem immediately |
Send break to remote modem immediately, then enter command mode |
Send break to DTE immediately | |
\K4 |
Enter command mode, do not send break to remote modem |
Send break to remote modem immediately |
Break sent with received data to the DTE | |
» \K5 |
Send break with transmitted data |
Send break to remote modem immediately |
Break sent with received data to the DTE |
CELLULAR TRANSMISSION LEVEL | |
Type: |
Configuration |
Format: |
AT [cmds] @Mn [cmds] |
Default: |
0 |
Range: |
11-31 |
Unit: |
-1dBm |
Description: |
Sets the signal level for transmission |
Command |
Function |
@M0 |
-26dBm |
@M1 |
-30dBm |
@M2-@M10 |
-10dBm |
CELLULAR TRANSMISSION LEVEL | |||
Format |
AT [cmds] S201=n [cmds] | ||
Default: |
58 | ||
Range: |
0-63 | ||
Unit: |
Bit-mapped | ||
Description: |
Controls cellular transmission level and compromise equalizer | ||
Bit |
Value |
Function | |
4 - 0 |
00000 00001 00010 ... 01010 01011 ... » 11010... 11111 |
Sets cellular transmit level level to -26dBm Sets cellular transmit level level to -30dBm Sets cellular transmit level level to -10dBm ... Sets cellular transmit level level to -10dBm Sets cellular transmit level level to -11dBm ... Sets cellular transmit level level to -26dBm ... Sets cellular transmit level level to -31dBm | |
5 |
0 » 1 |
Equalizer disabled Equalizer enabled |
CHANGE DIAL CODES | |
Type: |
Configuration |
Format: |
AT [cmds] *Zn [cmds] |
Description: |
Selects dial codes, for International use |
Command |
Function |
*Z0 |
Enable dial code 0 |
*Z1 |
Enable dial code 1 |
COMPRESSION | |
Type: |
Configuration |
Format: |
AT [cmds] %Cn [cmds] |
Description: |
Selects data compression |
Command |
Function |
%C0 |
Data compression disabled |
%C1 |
MNP5 enabled |
%C2 |
V.42bis enabled |
» %C3 |
MNP5 and V.42bis enabled |
COMPROMISE EQUALIZER | |
Type: |
Configuration |
Format: |
AT [cmds] :En [cmds] |
Description: |
Controls V.32 compromise equalizer |
Command |
Function |
:E0 |
Equalizer disabled |
» :E1 |
Equalizer enabled |
CONNECT MODE | |
Type: |
Configuration |
Format: |
AT [cmds] \Nn [cmds] |
Description: |
Sets connect mode |
Command |
Function |
\N0 |
Normal mode enabled |
\N1 |
Direct mode enabled |
\N2 |
Reliable mode enabled |
» \N3 |
Auto-reliable mode enabled |
\N4 |
LAPM mode enabled |
\N5 |
MNP mode enabled |
DIAL | |
Type: |
Immediate |
Format: |
AT [cmds] D<#> [cmds] |
Description: |
Dials telephone number according to any modifiers included in the string |
Modifier |
Function |
J |
Link will be negotiated at 1200bps |
K |
Power level adjustment enabled |
L |
Redials last valid dial string |
P |
Pulse dialing enabled |
S=c |
Number in memory location c dialed |
T |
Tone dialing enabled |
W |
Dialing resumed following dial tone detection |
@ |
Modem waits for a ring-back signal followed by silence up to the time specified in S7 prior to executing the rest of the dial string. |
! |
Flash function initiated Modem commanded to go on-hook for specified time |
; |
Modem returned to command mode after dialing |
^ |
Disable calling tone |
& |
Detect bong tone. Modem waits for time specified in S6 before returning NO DIALTONE. |
DISPLAY STORED NUMBERS | |
Type: |
Immediate |
Format: |
AT [cmds] \F [cmds] |
Description: |
Displays all stored phone numbers |
FLOW CONTROL | |
Type: |
Configuration |
Format: |
AT [cmds] \Gn [cmds] |
Description: |
Selects modem port flow control |
Command |
Function |
» \G0 |
Flow control disabled |
\G1 |
Flow control enabled |
FLOW CONTROL CHARACTER - XOFF | |
Type: |
Register |
Format: |
AT [cmds] S33=n [cmds] |
Default: |
19 |
Range: |
0-255 |
Unit: |
ASCII |
Description: |
Sets the character used to represent XOFF. |
FLOW CONTROL CHARACTER - XON | |
Type: |
Register |
Format: |
AT [cmds] S32=n [cmds] |
Default: |
17 |
Range: |
0-255 |
Unit: |
ASCII |
Description: |
Sets the character used to represent XON. |
LINE SIGNAL LEVEL | |
Type: |
Immediate |
Format: |
AT [cmds] %L [cmds] |
Range: |
9-43 |
Unit: |
-1dBm |
Description: |
Displays received line signal level |
MNP STREAM/BLOCK MODE | |
Type: |
Configuration |
Format: |
AT [cmds] \Ln [cmds] |
Description: |
Selects the transfer mode for MNP |
Command |
Function |
» \L0 |
Stream mode for MNP enabled |
\L1 |
Block mode for MNP enabled |
MNP10 COMPRESSION | |
Type: |
Configuration |
Format: |
AT [cmds] -Kn [cmds] |
Description: |
Selects MNP10 data compression |
Command |
Function |
-K0 |
MNP10 disabled |
» -K1 |
MNP10 enabled |
-K2 |
MNP10 enabled on originate mode only |
MAXIMUM BLOCK SIZE FOR TRANSMISSION | |
Type: |
Configuration |
Format: |
AT [cmds] \An [cmds] |
Description: |
Sets the maximum transmittable block size |
Command |
Function |
\A0 |
MNP block size is 64 characters |
» \A1 |
MNP block size is 128 characters |
\A2 |
MNP block size is 192 characters |
\A3 |
MNP block size is 256 characters |
MNP10 FALL-BACK | |
Type: |
Configuration |
Format: |
AT [cmds] -Qn [cmds] |
Description: |
Allows MNP10 to fall back to speeds slower than 4800bps |
Command |
Function |
-Q0 |
MNP10 at 2400 and 1200bps disabled |
» -Q1 |
MNP10 at 2400 and 1200bps enabled |
MNP10 LINK NEGOTIATION | |
Type: |
Configuration |
Format: |
AT [cmds] *Hn [cmds] |
Description: |
Sets the speed at which MNP10 link negotiation will occur |
Command |
Function |
» *H0 |
Link will be negotiated at highest possible speed |
*H1 |
Link will be negotiated at 1200bps |
*H2 |
Link will be negotiated at 4800bps |
Note: *H2 not supported with )M1 |
MNP10 POWER LEVEL ADJUST | |
Type: |
Configuration |
Format: |
AT [cmds] )Mn [cmds] |
Description: |
Controls automatic transmit power level adjustment during MNP 10 link negotiation |
Command |
Function |
» )M0 |
Power level adjustment disabled |
)M1 |
Power level adjustment enabled |
Note: )M1 not supported with *H2 |
MODULATION SELECTION DISPLAY | |
Type: |
Immediate |
Format: |
AT [cmds] +MSUnidentified [cmds] |
Description: |
Displays modulation, automode, minimum rate and maximum rate settings |
MODULATION SELECTION | |
Type: |
Configuration |
Format: |
AT [cmds] +MS=xx,y,zzz,aaa [cmds] |
Description: |
Sets options for active protocol. The transfer rates specified by z and a must be valid for the protocol selected |
Command |
Function |
x=0 |
V.21 |
x=1 |
V.22 |
x=2 |
V.22bis |
x=3 |
V.23 |
x=9 |
V.32 |
x=10 |
V.32bis |
» x=11 |
V.34 |
x=64 |
Bell 103A |
x=69 |
Bell 212A |
x=74 |
V.FC |
y =0 |
Automode disabled |
» y=1 |
Auto-detect highest speed enabled |
» z, a=300 |
Set minimum or maximum transfer rate at 300bps, respectively |
z, a =1200 |
Set minimum or maximum transfer rate at 1200bps, respectively |
z, a =2400 |
Set minimum or maximum transfer rate at 2400bps, respectively |
z, a =4800 |
Set minimum or maximum transfer rate at 4800bps, respectively |
z, a =7200 |
Set minimum or maximum transfer rate at 7200bps, respectively |
z, a =9600 |
Set minimum or maximum transfer rate at 9600bps, respectively |
z, a =12000 |
Set minimum or maximum transfer rate at 12000bps, respectively |
z, a =14400 |
Set minimum or maximum transfer rate at 14400bps, respectively |
z, a =16800 |
Set minimum or maximum transfer rate at 16800bps, respectively |
z, a =19200 |
Set minimum or maximum transfer rate at 19200bps, respectively |
z, a =21600 |
Set minimum or maximum transfer rate at 21600bps, respectively |
z, a =24000 |
Set minimum or maximum transfer rate at 24000bps, respectively |
z, a =26400 |
Set minimum or maximum transfer rate at 26400bps, respectively |
» z, a=28800 |
Set minimum or maximum transfer rate at 28800bps, respectively |
REPORT INFORMATION | |
Type: |
Immediate |
Format: |
AT [cmds] In [cmds] |
Description: |
Displays modem properties |
Command |
Function |
I0 |
Reports OK |
I1 |
Performs checksum of firmware ROM and displays results |
I2 |
Performs checksum of firmware ROM and displays status (OK or ERROR) |
I3 |
Reports firmware version, model code, interface type, and MCU model |
I4 |
Reports identifier string |
I5 |
Reports country code |
I6 |
Reports modem data pump model, internal code revision and CEP internal code revision. |
REPORT LINE SIGNAL QUALITY | |
Type: |
Immediate |
Format: |
AT [cmds] %Q [cmds] |
Description: |
Reports line signal quality. If the value is greater than 7, the modem will retrain. |
SLEEP TIMER | |
Format |
AT [cmds] S24=n [cmds] |
Default: |
0 |
Range: |
0-255 |
Unit: |
1 second |
Description: |
Maximum duration of DTE and DCE inactivity allowed prior to initiating low-power sleep mode. |
TEST MODES | |||
Format |
AT [cmds] S16=n [cmds] | ||
Default: |
0 | ||
Range: |
0-125 | ||
Unit: |
Bit-mapped | ||
Description: |
Controls loopback tests, analog, digital, remote digital, and self tests | ||
Bit |
Value |
Function | |
0 |
0 1 |
Local analog loopback not in progress Local analog loopback in progress | |
2, 1 |
0 |
Not used | |
3 |
0 1 |
Modem not in remote digital loopback Remote digital loopback in progress | |
4 |
0 1 |
Remote digital loopback not requested Remote digital loopback requested | |
5 |
0 1 |
Remote digital loopback w/ self-test not in progress Remote digital loopback w/ self-test in progress | |
6 |
0 1 |
Local analog loopback w/ self-test not in progress Local analog loopback w/ self-test in progress |
V.23 SPLIT BAUD MODE | |
Type: |
Configuration |
Format: |
AT [cmds] \Wn [cmds] |
Description: |
Controls V.23 split baud mode |
Command |
Function |
» \W0 |
V.23 split baud mode disabled |
\W1 |
V.23 split baud mode enabled |
V.23 SPLIT-SPEED DIRECTION | |
Type: |
Configuration |
Format: |
AT [cmds] %Fn [cmds] |
Description: |
Selects flow control |
Command |
Function |
%F1 |
75bps transmit/1200bps receive enabled |
%F2 |
75bps receive/1200bps transmit enabled |