Rs 232/Rs 485 Communication Description; Communication Protocol; Rs 232/Rs 485 Communication Description - Agilent Technologies TwisTorr Medium-TMP Mode D'emploi

RS 232/RS 485 Communication Description

Both the RS 232 and the RS 485 interfaces are available on the
connector P2.
The communication protocol is the same (see the structure below),
but only the RS 485 manages the address field. Therefore, to enable
the RS 485 is necessary to select the type of communication as well
as the device address by means of the serial communication software.
Communication Format

Communication Protocol

The communication protocol is a MASTER/SLAVE type where:
Host = MASTER
Controller = SLAVE
The communication is performed in the following way:
1. the host (MASTER) send a MESSAGE + CRC to the controller
(SLAVE);
2. the controller answer with an ANSWER + CRC to the host.
The MESSAGE is a string with the following format:
<STX>+<ADDR>+<WIN>+<COM>+<DATA>+<ETX>+<CRC>
where:
TwisTorr Medium-TMP onboard Controller User Manual / 87-901-050-01 (B)
Procedure to Connect the Serial and I/O Ports to an External Cable
•
8 data bit
•
no parity
•
1 stop bit
•
baud rate: 600/1200/2400/4800/9600 programmable
Technical Information
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