AT Commands and S-Registers
4-13
3825-A2-GB30-20
November 1996
Table 4-1
(11 of 14)
3825
Plus AT Commands
&X
n
Transmit Clock Source
Determines the source of timing for synchronous data transmitted from the DTE.
&X, &X0
Internal. Modem provides transmit clock source for synchronous data (Pin 15).
&X1
External. Modem derives external transmit clock source provided on Pin 24 for synchronous data.
&X2
Receive Clock Loop. Modem derives transmit clock source from receive signal for synchronous data (Pin 17).
&Z
n =x
Store Telephone Numbers
Modem saves the telephone number and dial command modifiers (if any) entered for
x (up to 40 characters in length) in
Directory Location
n (1–10). The DS command dials numbers stored this way.
For example, the command AT&Z1=5551234 stores the telephone number 555-1234 into directory location 1.
To clear a telephone number from a memory location, issue the &Z
n command without entering a telephone number.
% A
n
Error Control Fallback Character
This configuration option allows you to enter the ASCII value of the error control fallback character. This provides the
remote modem with the ability to end the error control link negotiating (handshaking) sequence by sending this character.
The modems will connect in Buffer mode (no error control). Online changes do not take effect until a disconnect occurs.
%A
n
Where
n is an ASCII value from 0 to 127. Factory default is 013 (ASCII carriage return).
%B
n, %BLn
Modulation/Data Rate
Sets the modulation and maximum dial VF rate. The same function can be performed with S-register S41; the %B and
%BL commands are provided for compatibility with environments where those commands are used.
The %B300 and %B1200 commands work in conjunction with the B (CCITT/ Bell Mode) command to determine
modulation.
The %B2400 through %B33600 commands set the modem for V.34 or V.34 extended operation, and the %BL2400
through %BL19200 commands set the modem for V.22bis, V.32, V.32bis, or V.32
terbo operation.
%B300
V.21 or Bell 103 — max. rate 300 bps
%B1200
V.22 or Bell 212A — max. rate 1200 bps
%B2400
V.34 — max. rate 2400 bps
%B4800
V.34 — max. rate 4800 bps
%B7200
V.34 — max. rate 7200 bps
%B9600
V.34 — max. rate 9600 bps
%B12000
V.34 — max. rate 12,000 bps
%B14400
V.34 — max. rate 14,400 bps
%B16800
V.34 — max. rate 16,800 bps
%B19200
V.34 — max. rate 19,200 bps
%B21600
V.34 — max. rate 21,600 bps
%B24000
V.34 — max. rate 24,000bps
%B26400
V.34 — max. rate 26,400 bps
%B28800
V.34 — max. rate 28,800 bps
%B31200
V.34 extended — max. rate 31,200 bps
%B33600
V.34 extended — max. rate 33,600 bps
%BL2400
V.22bis — max. rate 2400 bps
%BL4800
V.32bis/V.32 — max. rate 4800 bps
%BL7200
V.32bis — max. rate 7200 bps
%BL9600
V.32bis/V.32 — max. rate 9600 bps
%BL12000 V.32bis — max. rate 12,000 bps
%BL14400 V.32bis — max. rate 14,400 bps
%BL16800 V.32
terbo — max. rate 16,800 bps
%BL19200 V.32
terbo — max. rate 19,200 bps