User Guide

Table Of Contents
72
10. RS-232 Protocol
10.1 Introduction
This document describes the hardware interface spec and software protocols of
RS232 interface communication between ViewSonic LFD 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.
10.2 Description
10.2.1 RS232 Hardware Specication
ViewSonic LFD communication port on the rear side
(1) Connector type: DSUB 9-Pin Male (or 3.5mm barrel connector)
(2) Pin Assignment
(3) Use of crossover (null modem) cable for connection
Male DSUB 9-Pin
Male DSUB 9-Pin
Pin # Signal Remark
1 NC
2 RXD Input to Display
3 TXD Output from Display
4 NC
5 GND
6 NC
7 NC
8 NC
9 NC Proporciona alimentación de
+5V/2A para una llave externa
específica *3.0
frame GND