U.S. ROBOTICS, INC.
AUTO DIAL 21A
|
Card Type |
Modem (asynchronous) |
|
Chip Set |
U.S. Robotics |
|
Maximum Data Rate |
1200bps |
|
Data Bus |
External |
|
Data Modulation Protocol |
Bell 212A |
V2252
|
CONNECTIONS | ||||||
|
Function |
Label |
Function |
Label | |||
|
Line out/in - unidentified |
CN1 |
DC power |
CN4 | |||
|
Line in/out - unidentified |
CN2 |
Power switch |
SW1 | |||
|
RS-232/422 |
CN3 |
Analog loopback switch |
SW2 | |||
|
USER CONFIGURABLE SETTINGS | ||
|
Setting |
Label |
Position |
|
Auto answer disabled |
SW3/A |
Off |
|
Auto answer enabled |
SW3/A |
On |
|
CD normal |
SW3/B |
On |
|
CD forced high |
SW3/B |
Off |
|
Equalize for dial-up phone lines |
SW3/C |
Off |
|
Equalize for dedicated phone lines |
SW3/C |
On |
|
DTR normal |
SW3/D |
Off |
|
DTR forced high |
SW3/D |
On |
|
RS232C | ||||
|
Setting |
SW4/A |
SW4/B |
SW4/C |
SW4/D |
|
Pin 2 receive/Pin 3 send |
On |
On |
Off |
Off |
|
Pin 2 send/Pin 3 receive |
Off |
Off |
On |
On |
|
MISCELLANEOUS TECHNICAL NOTES |
|
Note: Diagram not available. |
|
DIAGNOSTIC LED(S) | |||
|
LED |
Color |
Status |
Condition |
|
CD |
Red |
On |
Carrier signal detected |
|
CD |
Red |
Off |
Carrier signal not detected |
|
HS |
Red |
On |
Modem is operating at 1200bps |
|
HS |
Red |
Off |
Modem is operating at slower than 1200bps |
|
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 |
|
RD |
Red |
On |
Modem is receiving data |
|
RD |
Red |
Off |
Modem is not receiving data |
|
AN |
Red |
On |
Auto-answer enabled |
|
AN |
Red |
Off |
Auto-answer disabled |
|
SD |
Red |
On |
Modem is transmitting data |
|
SD |
Red |
Off |
Modem is not transmitting data |
|
AL |
Red |
On |
Modem is in analog loopback test mode |
|
AL |
Red |
Off |
Modem is not in analog loopback test mode |
|
ON |
Red |
On |
Power is on |
|
ON |
Red |
Off |
Power is off |
Proprietary AT Command Set
|
ABORT | |
|
Type: |
Immediate |
|
Format: |
Any key |
|
Description: |
Aborts dialing command issued; modem hangs up. |
|
ANSWER | |
|
Type: |
Immediate |
|
Format: |
AT [cmds] A |
|
Description: |
Enables answer mode, the modem goes off-hook. |
|
ATTENTION | |
|
Type: |
Immediate |
|
Format: |
AT [cmds] |
|
Description: |
Tells the modem that a command follows or use alone to test OK result code |
|
DIAL | |
|
Type: |
Immediate |
|
Format: |
AT [cmds] D<#> [cmds] |
|
Example: |
ATDT 443-3388,,,1111; |
|
Description: |
Dials telephone number according to any modifiers included in the string |
|
Note: |
Any combination of modifiers can be used to produce the desired dial functions in sequence. |
|
Command |
Function |
|
í P |
Pulse dialing enabled |
|
T |
Tone dialing enabled |
|
, |
Dialing paused for 2 seconds |
|
ECHO | |
|
Type: |
Configuration |
|
Format: |
AT [cmds] En [cmds] |
|
Description: |
Controls echo function; display keyboard commands when enabled. |
|
Command |
Function |
|
í E0 |
Echo function disabled |
|
E1 |
Echo function enabled |
|
ECHO - ON-LINE | |
|
Type: |
Configuration |
|
Format: |
AT [cmds] Fn [cmds] |
|
Description: |
Selects whether commands sent while in data mode are echoed |
|
Command |
Function |
|
F0 |
Local echo enabled |
|
í F1 |
Local echo disabled |
|
ESCAPE SEQUENCE | |
|
Type: |
Immediate |
|
Format: |
+++AT [cmds] <CR> |
|
Description: |
Initiates the escape sequence and returns the modem to the on-line command state if it receives three escape characters set in S2 within the time allotted by S12. |
Note: Do not precede this command with AT. | |
|
PULSE DIALING | |
|
Type: |
Configuration |
|
Format: |
AT [cmds] P [cmds] |
|
Description: |
Enables pulse dialing |
Note: This command can be duplicated with the P modifier in the D (Dial) command. | |
|
REPEAT PREVIOUS COMMAND | |
|
Type: |
Immediate |
|
Format: |
A/ |
|
Description: |
Repeats previous command, mainly used for redial |
Note: Do not precede this command with AT, or follow it with <CR>. | |
|
RESET | |
|
Type: |
Immediate |
|
Format: |
AT [cmds] Z [cmds] |
|
Description: |
Resets the modem and clears all registers to default values |
|
RESULT CODES | |
|
Type: |
Configuration |
|
Format: |
AT [cmds] Qn [cmds] |
|
Description: |
Enables modem to send result codes to the DTE |
|
Command |
Function |
|
í Q0 |
Result code sending enabled |
|
Q1 |
Result code sending disabled |
|
RESULT CODE FORMAT | |
|
Type: |
Configuration |
|
Format: |
AT [cmds] Vn [cmds] |
|
Description: |
Selects word or numeric format for information-text and result codes |
|
Command |
Function |
|
V0 |
Numeric format enabled |
|
í V1 |
Verbose (word) format enabled |
|
SELECT CALL PROGRESS RESULT CODES | |
|
Type: |
Configuration |
|
Format: |
AT [cmds] Xn [cmds] |
|
Description: |
Enables selection of tone detection and associated result code format options |
|
Command |
Function |
|
í X0 |
Extended result codes disabled; result codes 0-4 enabled. |
|
X1 |
Extended result codes enabled; result codes 0-5 enabled |
|
SPEAKER MODE | |
|
Type: |
Configuration |
|
Format: |
AT [cmds] Mn [cmds] |
|
Description: |
Selects various speaker options |
|
Command |
Function |
|
M0 |
Speaker disabled |
|
í M1 |
Speaker enabled until carrier signal detected |
|
M2 |
Speaker enabled |
|
STATUS-REGISTER | ||
|
Type: |
Configuration | |
|
Format: |
AT [cmds] Sn=x [cmds] | |
|
Description: |
Writes to a specified register, values ranging from 0-255. | |
|
Command |
Function | |
|
S0=x |
Sets the number of rings allowed before the modem automatically goes off-hook. S0=0 will disable auto-answer. | |
|
S2=x |
Selects a character used for the escape sequence. Default = 43 | |
|
S7=x |
Maximum wait time in seconds the modem uses after dialing to detect a carrier signal from the remote modem for both originating and answering calls. Default = 30 | |
|
TONE DIALING | |
|
Type: |
Configuration |
|
Format: |
AT [cmds] T [cmds] |
|
Description: |
Enables tone dialing mode |
Note: This command can be duplicated with the T modifier in the D (Dial) command. | |