Siemens SITRANS F Operating Instructions Manual page 35

The starting register is the first register that was written to.
The quantity value indicates how many consecutive registers were written to.
Table 6- 12
Message byte
Slave address
Function code
Starting register
Quantity
CRC-16
Exception responses
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 10 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- 13
Message byte
Slave address
Function code
Exception code
CRC-16
Example
Set baud rate to 38400 baud
● Query: 1,16,2,17,0,1,2,0,5,70,210 (38400 = value 5) (Hex
01,10,02,11,00,01,02,00,05,46,D2)
● Normal response: 1,16,2,17,0,1,80,116 (Hex 01,10,02,11,00,01,50,74)
To activate a new baudrate and parity/framing the coil 0 (Restart Modbus communication)
must be sent.
MAG 8000 Modbus RTU
Operating Instructions, 04/2016, A5E03409989-AB
Write multiple coil normal response messages
Upper
Lower
Upper
Lower
Lower
Upper
Write multiple coil exception response messages
Lower
Upper
Function codes
6.5 Write multiple registers
Example
xx hex
10 hex
xx hex
xx hex
xx hex
xx hex
xx hex
xx hex
Example
xx hex
90 hex
01 hex to 06 hex
xx hex
xx hex
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