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XTX-7500 – USER MANUAL – ENGLISH
SERIAL COMMANDS
10.3. COMMAND AND RESPONSE FORMAT
Commands sent from an automation/control
system or PC to the display must have the following
format:
[STX] [IDT] [TYPE] [CMD] ([VALUE] or [REPLY]) [ETX]
[CR]
Where:
• [STX] indicates the start of the command data
(always 07).
• [IDT] is the display ID (always 01).
• [TYPE] is the command type:
•
00 = return to host (response from the
LCD panel)
•
= read / action
•
= write
• [VALUE] is the parameter setting for the command.
• [REPLY] is the parameter setting for the command,
acknowledged by the display in its response to a
command.
• [ETX] indicates the end of the command data
(always 08).
• [CR] is the ASCII carriage return key (0x0D).
10. SERIAL COMMANDS
10.1. SERIAL COMMUNICATIONS
10.2. RS-232 CONNECTION AND PORT CONFIGURATION
The display uses a simple text-based control protocol to take requests from control devices and to provide
responses to such devices. This section describes how to send control messages over a serial link between the
display and an automation/control system or a PC running a terminal emulation program such as Windows
®
HyperTerminal or Tera Term.
Connect your control system or PC to the RS-232 input of the display.
Configure the RS-232 controller or PC serial port as follows: no parity, 8 data bits, 1 stop bit and no flow control.
Set the baud rate to 115200, to match that of the display RS-232 port.
