What do you want to do?
Build a request frame
Decode a captured frame
Calculate or check a CRC-16
Slave address (1 to 247)
Function
03 Read holding registers
04 Read input registers
01 Read coils
02 Read discrete inputs
05 Write single coil
06 Write single register
16 Write multiple registers
Start address (as sent, 0 to 65535)
Holding register 40001 is address 0.
Quantity of registers
Values to write (decimal, separated by commas)
Bytes in hex (spaces, commas or 0x are fine)
01 03 04 00 0A 01 02 5A 60
Baud rate
1 200
2 400
4 800
9 600
19 200
38 400
57 600
115 200
Character format
8N1 (10 bits)
8E1 or 8O1 (11 bits)
8N2 (11 bits)
Slave processing time (ms)
Frame with CRC
CRC-16 (low byte first)
Breakdown
Timing
Calculator by
Engineer Underground
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