ViewSonic CDE3200-L, User Manual

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26
RS232 Protocol
1. Introduction
This document describes the hardware interface spec and software protocols of
RS232 interface communication between Viewsonic Commercial Display and PC or
other control unit with RS232 protocol.
The protocol divide into three sections:
• Set-Function
• Get-Function
• Remote control pass-through mode
※
In below document, “PC” will represents all the control units that can sent or
receive the RS232 protocol command.
2. Description
2.1 Hardware specification
Viewsonic communication port in the rear side
(1) Connector type: DSUB 9 Pin Male
(2) Pin Assignment
Male DSUB 9Pin
(outside view)
Pin # Signal Remark
1 NC
2 RXD Input to Monitor
3 TXD Output from Monitor
4 NC
5 GND
6 NC
7 NC
8 NC
9 NC
frame GND
* Use of crossover (null modem) cable required for
use with PC.
2.2 Communication Setting
• Baud Rate Select: 9600bps (fixed)
• Data bits: 8bits (fixed)
• Parity: None (fixed)
• Stop Bits: 1 (fixed)
2.3 Command Message Reference
PC sends to Monitor command packet followed by “CR”. Every time PC sends
control command to the Monitor, the Monitor shall response as follows:
1. If the message is receives correctly it will send “+” (02Bh) followed by “CR” (00Dh)
2. If the message is receives incorrectly it will send “-” (02Dh) followed by “CR”
(00Dh)