wtw TresCon UNO A111, Руководство по эксплуатации

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Appendix TresCon UNO
8 - 6 ba43134e08 05/2017
The command section contains:

the address of the Slave,

the command to be executed (message section) and

the CRC check (Cyclic Redundancy Check).
The command to be executed is imported by the Slave and correspon-
dingly evaluated.
The response section contains a message on the correct BUS trans-
fer and, if necessary, data.
Data format Hardware RS485 / 2-wire (Half-Duplex); the baud rate is permanently
set to 9600 baud, 8 data bits, no parity.
Slave addresses: 01 to 31; 00 = "Broadcast address" (message for all).
1 byte 1 byte n bytes 2 bytes
Slave address
Status bits Length infor-
mation
n+2 ASCII
message CRC16
(CCITT-X.25)
7 6 5 4 3 2 1 0
Always
1 Master/
Slave Error Slave address 01 to 31,
00 = broadcast
Bit 7 "1" always 1
Bit 6 Master/Slave "1" indicates that the message has
been sent from the Master to the Slave.
The Slave address addresses the data sink.
"0" indicates that the message is a response from
the Slave to the Master. The Slave address then
specifies the data source.
Bit 5 Error: during transmission from Master--> Slave
always "1"/ for a syntax error, it is set by the Slave
bit to 0.
Bit 4,3,2,1,0 Slave address 1 to 31; 00 = "broadcast"
The address 00 addresses all slaves; there is no
feedback from the slaves; the address 00 is for cer-
tain commands allowed only.
Structure of a message
Slave address,
Status bit