Viewsonic CD4620 ユーザーズマニュアル

 CD4620 

45 

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. 
Viewsonic CD4620 and CD4220 contain with 2 set of protocol command 
1. 

This set protocol allow user to assign the ID in the command to control the specify ID monitor 
2. 

The set protocol is best for single display control and for Viewsonic NMP-530. 
 
Both sets protocol contain three sections command: 

z

 Set-Function 

z

 Get-Function 

z

 

Remote control pass-through mode 

※

In below document, “PC” will represents all the control units that can sent or receive the RS232 

protocol command. 

Viewsonic LCD communication port in the rear side   
(1) Connector type: DSUB 9 Pin Male   
(2) Pin Assignment   
 

Male DSUB 9Pin 

 

(outside view) 

 

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 

  - Baud Rate Select: 

9600bps (fixed)   

  - Data bits:   

8bits (fixed)   

  - Parity:   

None (fixed)   

 - Stop Bits:  

1(fixed)  

 

4.3  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)