Agilent Technologies TV-401/301/21 NSF, Руководство пользователя

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Technical Information
RS 232/RS 485 Communication Description
260/294 TV 401/301/21 NSF User Manual / 87-900-995-01 (C)
RS 232/RS 485 Communication Description
Both the RS 232 and the RS 485 interfaces are available on the
connector J6.
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
ƒ
8 data bit
ƒ
no parity
ƒ
1 stop bit
ƒ baud rate: 600/1200/2400/4800/9600 programmable
Communication Protocol
The communication protocol is a MASTER/SLAVE type where:
ƒ Host = MASTER
ƒ
Controller = SLAVE
The communication is performed in the following way:
1. the host (MASTER) send a M CRC to the controller
(SLAVE);
2. the controller answer with an CRC to the host.
The MESSAGE is a string with the following format:
<STX>+<ADDR>+<WIN>+<COM>+<DATA>+<ETX>+<CRC>
where: