User Guide

RS232 Protocol

1. Introduction

This document describes the hardware interface spec and software protocols

of RS232 interface communication between ViewSonic Commercial TV / Digital

Signage and PC or other control unit with RS232 protocol.

The protocol contains three sections command:

• Set-Function

• Get-Function

• Remote control pass-through mode

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

receive the RS232 protocol command.

2. Description

2.1 Hardware specification

Viewsonic TV communication port on the rear side

(1) Connector type: DSUB 9-Pin Male

(2) Pin Assignment

Male DSUB 9-Pin

(outside view)

Pin # Signal Remark

1 NC

2 RXD Input to Commercial TV or DS

3 TXD Output from Commercial TV or DS

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 respond as follows:

1. If the message is received correctly it will send “+” (02Bh) followed by “CR” (00Dh)

2. If the message is received incorrectly it will send “-” (02Dh) followed by “CR”

(00Dh)