Black Box MD1640A Enable/Disable V.25bis Mode $V Command, Change Serial Baud Rate CSP Command

APPENDIX G: V.25bis Operation

Enable/Disable V.25bis Mode ($V) Command

The function of the $V command is to select the V.25bis mode in asynchronous mode. (Synchronous mode is set up with switches. For example, the modem could be in AT command mode, (AT$V1), and if synchronous mode is enabled with AT Command mode enabled, then V.25bis 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.25bis mode, most normal AT commands will also function (except D,N,O and U). V.25bis 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 synchro- nization.

To place your modem in V.25bis 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.25bis command from AT command mode without leaving AT command mode (the V.25bis 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 CSPsssss 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

179