FSR IT-VCM - Manual (Page 3)

Page 3 of 16
Serial Protocol
The protocol for the IT-VCM is a pure ASCII protocol. Each serial command begins with a three
character serial request. An ASCII space character "
_ " is used between fields in the request except
for the last field that is immediately followed by a carriage return (, 0x0D). Only one space
will be accepted between the fields, any less or more spaces, or tabs will result in an error message
being returned.
After the IT-VCM responds to a controller request, it will send a prompt to the controller. The
prompt is a carriage return (0x0D), line feed (0x0A), and a right arrow character ">". The purpose
of the prompt is to keep the display legible while typing on a terminal, hyper-terminal, or controller
terminal program.
The Serial-In port is configured for 38,400 baud, 8 data bits, 1 stop bit, and no handshaking. Serial-
In configuration cannot be changed. The Serial Output baud rate can be changed via the Serial baud
rate request "SBA".
Typical RS-232 Device Interconnections
The table below details the typical hookup for RS-232 control of the IT-VCM module.
Connections for loop through applications are included.
IT-VCM