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FnIO MODBUS Adapter NA-9189
FnIO S-Series
Copyright(C) CREVIS Co.,Ltd Support +82-31-273-6453 URL : www.crevis.co.kr
6.2.1.
1 (0x01) Read Coils
This function code is used to read from 1 to 2000 contiguous status of coils in a remote device. The Request PDU
specifies the starting address, i.e. the address of the first coil specified, and the number of coils. In the PDU Coils
are addressed starting at zero. Therefore coils numbered 1-16 are addressed as 0-15. The coils in the response
message are packed as one coil per bit of the data field. Status is indicated as 1= ON and 0= OFF.
Request
Field name
Example
Function Code
0x01
Starting Address Hi
0x10
Starting Address Lo
0x00
Quantity of Output Hi
0x00
Quantity of Output Lo
0x0A
Response
Field name
Example
Function Code
0x01
Byte Count
0x02
Output Status
0x55
Output Status
0x02
-
In case of address 0x1015~0x1000 output bit value: 00000010_01010101
.
6.2.2.
2 (0x02) Read Discrete Inputs
This function code is used to read from 1 to 2000 contiguous status of discrete inputs in a remote device. The
Request PDU specifies the starting address, i.e. the address of the first input specified, and the number of inputs. In
the PDU Discrete Inputs are addressed starting at zero. Therefore Discrete inputs numbered 1-16 are addressed as
0-15. The discrete inputs in the response message are packed as one input per bit of the data field.
Status is indicated as 1= ON; 0= OFF.
Request
Field name
Example
Function Code
0x02
Starting Address Hi
0x00
Starting Address Lo
0x00
Quantity of Inputs Hi
0x00
Quantity of Inputs Lo
0x0A
Response
Field name
Example
Function Code
0x02
Byte Count
0x02
Input Status
0x80
Input Status
0x00
-
In case of address 0x0015~0x0000 output bit value: 00000000_10000000.
