98
MultiModemBA User Guide
V.25bis Responses (Result Codes)
When in V.25
bis
mode (the
AT$V1
command executed), your modem provides you with several
responses which can help you follow the progress of V.25
bis
operations. These are similar to the
Result Codes associated with AT Command mode operation. The V.25
bis
responses are in the form
of three-character mnemonics as listed below:
INC Incoming Call (same as RING indicator)
VAL A valid V.25
bis
command has been attempted
DLC
t
Call delayed for
t
minutes (number on Delayed list)
CFl
rr
Call failure indicator where
rr
equals:
et
- Engaged tone (same as BUSY)
nt
- Call Answered but No Answer Tone
ab
- Call Not Answered
fc
- Number on Forbidden List
ns
- Number not stored in memory
ua
- User Abort
nd
- No Dialtone
ff
- Forbidden List full
LSN
mm;dd...dd
Phone number in V.25
bis
memory
LSD
mm;dd...dd
Phone number on the Delay list
LSF
mm;dd...dd
Phone number on the forbidden list
CON
ssss
Connection at ssss speed (if X1 in effect)
V.25bis AT Commands
The AT commands associated with V.25
bis
mode are described as follows. Note that one command
enables and disables V.25
bis
mode and the rest are only operable in the V.25
bis
mode.
Enable/Disable V.25bis Mode ($V) Command
The function of the
$V
command is to select the V.25
bis
mode in asynchronous mode. (Synchronous
mode is set up with switches. For example, the modem could be in AT command mode, (
AT$V1
),
and if synchronous mode is enabled with AT Command mode enabled, then V.25
bis
mode is
selected). Prior to executing this command, make sure that your modem is properly set up to perform
the type of operation you will be performing. Refer to the initialization section of this appendix for
information about modem set-up. When in V.25
bis
mode, most normal AT commands will also
function (except
D
,
N
,
O
and
U
). V.25
bis
operates in asynchronous or synchronous modes (depending
on the position of DIP-Switch #12), and does not check for terminal speed (so do not change speeds
while in this mode) or parity. In synchronous mode, speed is not important since the internal clocks
provide synchronization.
To place your modem in V.25
bis
mode from asynchronous mode, enter the
AT$V1
command. To
return to AT command mode, enter the
AT$V0
command.
AT$V2
allows you to run one V.25
bis
command from AT command mode without leaving AT command mode (the V.25
bis
command
follows
$V2
on the command line).
Change Serial Baud Rate (CSP) Command
The
CSP
command will change the serial baud rate of your modem by entering CSP
sssss
where
sssss
can equal:
0300 = 300 bps
1200 = 1200 bps
2400 = 2400 bps
4800 = 4800 bps
9600 = 9600 bps
19200 = 19200 bps
38400 = 38400 bps
57600 = 57600 bps
115200 = 115200 bps