ViewSonic CD4233 - 2 Description; Hardware Specification; Communication Setting; Command Message Reference

Commercial Display RS-232 Protocol
Revision 1.x
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May 28, 2007 2 / 16 Commercial Display RS-232 Protocol
This set protocol allow user to assign the ID in the command to control the specify ID monitor
2. Protocol 2, without ID
The set protocol is best for single display control and for Viewsonic NMP-530.
Both sets protocol contain three sections command:
 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 LCD 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 LCD Monitor
3
TXD
Output from LCD 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)
3 Protocol 1 : with ID
3.1 Command Description
Length:
Total Byte of Message excluding “CR”