High−level Instructions
3 − 374
Command 03 (Holding register read)
Example) When 6 words are read from the address H7788 of the unit No. 17 connected to the COM1 and
written in the area starting with DT100 in the local unit.
[ F146(RECV), H1311,H7788, K6, DT100 ]
[S1]: H1 H1 H1
Unit No. (H01 to HFF)Selects COM port
H3
Command
conversion
[S1]:H1311
[S2]:H7788
[N] :K6
[D] :DT100
MODBUS commands
Slave address
Command (03H)
Starting No. of read (H)
Starting No. of read (L)
Quantity to read (H)
Quantity to read (L)
CRC16 (H)
CRC16 (L)
11
03
77
88
00
06
5C
C6
1
2
3
4
5
6
7
8
Command 04 (Input register read)
Example) When 6 words are read from the address H7788 of the unit No. 17 connected to the COM1 and
written in the area starting with DT100 in the local unit.
[ F146(RECV), H1411,H7788, K6, DT100 ]
Command
conversion
[S1]:H1411
[S2]:H7788
[N] :K6
[D] :DT100
MODBUS commands
Slave address
Command (04H)
Starting No. of read (H)
Starting No. of read (L)
Quantity to read (H)
Quantity to read (L)
CRC16 (H)
CRC16 (L)
11
04
77
88
00
06
E9
06
1
2
3
4
5
6
7
8
Flag conditions
Σ Error flag (R9007) :
Σ Error flag (R9008) :
− Turns on when the control data of [S1] is a value outside of the specified
range.
− Turns on when the MODBUS mode has not been specified for the COM
port of the control data specified by [S1].
− Turns on when the number of received data N is 0.
− Turns on when the number of received data is negative.
− Turns on when the number of received data [N] exceeds the limit of the
MODBUS specifications.
− Turns on when the number of received data [N] exceeds the operation
memory area specified by [D].
FPΣ/FP−X/FP0R
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