Autonics KPN Series, User Manual For Communication

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1 Modbus RTU protocol
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1 Modbus RTU protocol
1.1 Read Coil Status(Func01–01H)
Reads the output (OX reference, Coil) ON/OFF status in Slave device.
1) Query(Master)
Slave Address Function
Starting Address No. of Points Error Check(CRC16)
High Low High Low Low High
1Byte 1Byte 1Byte 1Byte 1Byte 1Byte 1Byte 1Byte
2) Response(Slave)
Slave Address Function Byte Count Data Data Data
Error Check(CRC16)
Low High
1Byte 1Byte 1Byte 1Byte 1Byte 1Byte 1Byte 1Byte
If read the output status(ON: 1, OFF: 0) of 10EA within coil 000001(0000 H) to
000010(0009 H) on Slave side(Address 17) from Master side.

Query(Master)
Slave Address Function
Starting Address No. of Points Error Check(CRC16)
High Low High Low Low High
11 H 02 H 00 H 00 H 00 H 0A H ## H ## H
If the values range from coil 000008(0007 H)
to
000001(0000 H) on the slave side are
“
ON-ON-OFF-OFF-ON-ON-OFF-ON”, and the values from 000010(0009 H) to
000009(0008 H) are respectively “OFF-ON”.

Response(Slave)
Slave Address Function Byte Count
Data
(000008 to
000001)
Data
(000010 to
000009)
Error Check(CRC16)
Low High
11 H 01 H 02 H CD H 01 H ## H ## H
CRC16
CRC16