GPO US 70M, User Manual, Page: 21 / 25

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User manual
Commercial
LCD Series
This document defines all the command and messages exchanged between the Master (a PC or the other
controller) and the Slave (the displays).
It also describes the ways to send or read the commands or the messages.
1. Protocol definition
SICP stands for “Serial Interface Communication Protocol”.
The protocol is specifically designed to allow data communication in half duplex multi-point environments,
but it can also be used for half duplex point-to-point RS-232C communication.
2. Communication characteristics
A half duplex communication is implemented starting from the concept of a master-slave structure, where
the display is supposed to be the slave.
The first action is always taken by the master, which can be either a PC or any controlling device (acting as
server) interfaced to the monitor. After sending a command or a request in the appropriate format the
master receives from the slave an acknowledgement, which tells the transmitter whether the command is
not valid (or not executable, anyway) or it is accepted. In case of a request, the requested information is sent
back and it becomes the acknowledgement by itself.
3. How to connect control devices
Female Pin number Male Pin number
2 <------------------------------------------------------> 2
3 <------------------------------------------------------> 3
5 <------------------------------------------------------> 5
4. Hardware Protocol
Baud rate : 9600 bps
Data bits : 8 bit
Parity bits : None
Stop bits : 1 bit
Handshake : None
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SICP (Serial Interface Communication Protocol)