Siemens SITRANS F Operating Instructions Manual page 33

The new coil value is the value written to the coil.
Table 6- 9
Message byte
Slave address
Function code
Coil address
New coil value
CRC-16
Exception response
The exception response message contains the same slave address as the command
message.
The function code of the exception message is actually a value of 80 hex plus the original
function code of 05 hex. The exception code indicates where the error occurred in the
command message. A complete listing of exception codes is shown in Exception handling
(Page 35).
Table 6- 10
Message byte
Slave address
Function code
Exception code
CRC-16
Examples
Coil 0 (Restart Modbus communication)
To activate a new baudrate and parity/framing the coil 0 (restart Modbus communication)
must be sent. Otherwise a power down/up initiate a new baudrate and parity/framing:
● Query: 1,5,0,0,255,0,140,58 (Hex 01,05,00,00,FF,00,8C,3A) (Set coil 0 to 0xFF00)
● Normal response: 1,5,0,0,255,0,140,58 (Hex 01,05,00,00,FF,00,8C,3A) (Restart Modbus
communication)
MAG 8000 Modbus RTU
Operating Instructions, 04/2016, A5E03409989-AB
Write coil normal response messages
Upper
Lower
Upper
Lower
Lower
Upper
Write coil exception response messages
Lower
Upper
Function codes
6.4 Write single coil
Example
xx hex
05 hex
xx hex
xx hex
FF hex or 00 hex
00 hex
xx hex
xx hex
Example
xx hex
85 hex
01 hex to 06 hex
xx hex
xx hex
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