Introduction; Description - ViewSonic IFP5550 User Manual

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 Hardware Specification
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
3.5mm barrel connector
(alternative for limited
space)
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
frame GND
Pin # Signal
Tip TXD
Ring RXD
Sleeve GND
79
Remark
Output from Display
Input to Display