phytron MSD2+, Руководство пользователя

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phytron
39 MA 2126
–A005 EN
10 Configuration in the ServiceBus (RS485-4-wire)
The operating parameters in the MSD2
+
can be set by the RS 485 serial bus connection
(ServiceBus).
The instruction set and more information about the ServiceBus see chap.10.2.
10.1 Bus Connection
A well-defined protocol should be followed to assure a safe data exchange:
Asynchronous transmission, 8 bits/byte, 1 stop bit, 1 parity bit
Transmission rate: 57600 Baud
Permanent telegram format:
<STX> <address_H><address_L> <instruction> <value> : <csh> <csl> < ETX>
<STX> Start-of-text character, 02
H
<address_H> High-order byte of the power stage address 00
H
...0F
H
,
0
D
…15
D
;
Admissible characters: 0…F
<address_L> Low-order byte of the power stage address 00
H
...0F
H
,
0
D
…15
D
;
Admissible characters: 0…F
<instruction> Instruction byte: A....Z
<value> Data byte
: Colon as separator, to distinguish between usable data
and checksum
<csh> Upper byte of the 8 bit checksum value
<csl> lower byte of the 8 bit checksum value
< ETX> End-of-text character, 03
H