Tadpole SPARCbook 3 series, Reference Manual

Page: 125 / 216

MODEM
9-7
AT Command Set
With the exception of A/, all command lines begin with the attention
characters “AT” followed by one or more command characters, and are
terminated with a
RETURN
. Command lines may contain up to 56
characters, including A and T. All characters before the AT string, and all
characters that follow an errant command are ignored.
The modem can be returned to normal operation by typing in
~.
(tilde
period).
Note
Normally, a host computer and modem communicate via a serial link, but in the
SPARCbook application, the MCU and DPL chipset present a parallel interface to
the host and are themselves interconnected via an asynchronous parallel interface.
The commands which relate to the control of a serial link between a host and modem
have no effect on the operation of the SPARCbook modem.
A Answer Incoming Call
This forces the modem to go off-hook in answer mode.
A/ Re-execute Previous Command
This repeats the last command. It is not preceded by the AT
characters or terminated by pressing
RETURN
.
AT ATtention Characters
These characters must appear at the beginning of all
command lines.
Bn Bell/CCITT Protocol
This command selects the communication standard:
n = 0 CCITT operation
n = 1 Bell
Dn Dial Telephone Number
This command causes the modem to dial up a remote
modem. The following modifiers may be added:
L Redial last number
P Pulse Dialling
T Touch-tone Dialling
R Originate Call in Answer Mode
W Wait for dial tone for a time defined by S6
, Delay dial sequence for a time defined by S8
@ Wait for Quiet for a time defined by S7
! Go On-hook for a time defined by S29
; Return to Command Mode
S=n Dial a Stored Number
S3GX_TRMBook Page 7 Friday, September 19, 1997 11:39 am