Chapter 3 - AT Commands, S-Registers, and Result Codes
Basic AT Commands
Command Function (* indicates factory default setting)
A/Re-execute the last command string.
<any key> Terminate the current connection attempt when entered in handshaking state.
The following commands require an “AT” prefix.
A | Go |
Bn | Line modulation options |
B0 | Select V.22 mode for 1200 bps connection |
B1 * | Select Bell 212A for 1200 bps connection |
B2 | Select V.23 1200 bps for receiving, 75 bps for transmitting in originate mode; 75 bps |
| for receiving and 1200 bps for transmitting in answer mode |
B3 | Select V.23 75 bps for receiving, 1200 bps for transmitting in originate mode; 1200 |
| bps for receiving and 75 bps for transmitting in answer mode |
B15 | Select V.21 for 300 bps connection |
B16 | Select Bell 103 for 300 bps connection |
Dn | Dial command, beginning the dialing sequence. The string “n” (telephone number |
| and modifiers) listed as follows is entered after the “D” command |
L | |
P | Pulse dial |
R | Reverse dial. Originate call in answer mode (go |
S=n | Dial the phone number stored in NVRAM at location “n” (n=0, 1, 2, 3) |
T | DTMF tone dial |
WWait for second dial tone. The modem waits for the second dial tone before processing the dial string Pause. Cause the modem to pause for a time before processing the next character in the dial string (specified by S8 register)
!Hook Flash (for call transfer). Cause the modem to go
@Wait for 5 seconds of silence after dialing number
;Return to command state after dialing a number without disconnecting the call
En | AT command echo options |
E0 | Echo disabled |
E1 * | Echo enabled |
Hn | |
H0 * | Modem goes |
H1 | Modem goes |
Mn | Speaker control |
M0 | Speaker always off |
M1 * | Speaker on until carrier present |
MT5634ZLX/FE | 37 |