The quantity value indicates how many consecutive registers were written to.
Table 6-12 Write multiple coil normal response messages
Message byte Example
Slave address xxhex
Function code 10hex
Starting register Upper xxhex
Lower xxhex
Quantity Upper xxhex
Lower xxhex
CRC-16 Lower xxhex
Upper xxhex
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 a later chapter.
Table 6-13 Write multiple coil exception response messages
Message byte Example
Slave address xxhex
Function code 90hex
Exception code 01hex to 06hex
CRC-16 Lower xxhex
Upper xxhex
Example
Set baud rate to 115200 baud
• Query: 1,16,2,17,0,1,2,0,8,135,23 (115200 = value 8) (Hex
01,10,02,11,00,01,02,00,08,87,17)
• Receive: 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 send.
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)
• Receive: 1,5,0,0,255,0,140,58 (Hex 01,05,00,00,FF,00,8C,3A) (Restart Modbus
communication)
Functions codes
6.5 Write multiple registers
Modbus RTU RS 485
Operating Instructions, 03/2021, A5E00753974-AB 31
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