Serial Communication, cont’d
DVS 150 Serial Communication4-2
Serial Communication
The scaler’s RS-232 connector can be connected to the serial port output of a host
device such as a computer or control system. This connection makes software
control of the scaler possible. Figure 10 shows a scaler RS-232 connection to a host
serial port connector.
Figure 10 — Scaler RS-232 to host connection
The RS-232 connector on the scaler is a 9-pin D female connector with the following
pin assignments:
Pin Description
1 Input 1 select*
2 Transmit data
3 Receive data
4 Input 2 select*
5 Signal ground
6 Input 3 select*
7 Input 4 select*
8 Not used
9 Not used
* Used for remote contact closure control
The protocol is 9600 baud, 8-bit, 1 stop bit, no parity, and no flow control.
The scaler accepts SIS™ (Simple Instruction Set™) commands through the RS-232
port. SIS commands consist of one or more characters per command field. They do
not require any special characters to begin or end the command character sequence.
Each scaler response to an SIS command ends with a carriage return and a line feed
(CR/LF = ), which signals the end of the response character string. (A string is
one or more characters.)

RS-232 Programmer’s Guide

DVS initiated messages

When a local event occurs, such as a front panel operation, the scaler responds by
sending a message to the host. The DVS-initiated messages are listed below
(underlined).
(C) Copyright 1999, Extron Electronics, DVS 150, Vx.xx
The copyright message is initiated by the scaler when it is first powered on. Vx.xx
is the firmware version number.
Reconfig
The Reconfig message is initiated by the scaler when a new input is selected or
when any image adjustment is made.
The scaler does not expect a response from the host, but, for example, the host
program might request a new status.
RS-232
Control Cable
DVS 150
H
R
V
G
S
B
REMOTE
RGB
OUTPUTS
Computer Control