Rs 232/Rs 485 Communication Description; Communication Protocol - Agilent Technologies TV 551 Navigator User Manual

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 Navigator software.
Communication Format
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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:
When a data is indicated between two quotes ('...') it means that the indicated
NOTE
data is the corresponding ASCII character.
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TV 551/701 Navigator User Manual / 87-900-934-01 (P)
How to Connect the Open-Collector Inputs of the Controller
8 data bit
no parity
1 stop bit
baud rate: 600/1200/2400/4800/9600 programmable
<STX> (Start of transmission) = 0x02
Technical Information
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