MODBUS TCP Master/Slave Communication
6.3.3 RECV Command (MODBUS Function Code Unspecified Type)
Command format
Operand
Items Settings Setting range
i Specify the operation unit. US / SS
S1 Specify the partner station no. H1 - HF7 (1 - 247)
S2
Specify the device initial address of the source node data area in the
partner node.
(Note 1) (Note 2)
H0 - HFFFF (0 - 65535)
n Specify the No. of sent data. (Note 3)
1 - 127 words
1 - 2040 bits
D1
Specify the device initial address of the receiver node data area in the
source node. (Note 1)
(Note 4)
D2
Specify the device area in the source node to save the execution result
code (one word).
(Note 5)
(Note 1) Types of devices and transmission methods to be specified for operands [S2] and [D1], and MODBUS
function codes to be used for command execution vary.
Device to be specified
for [S2] and [D1]
Transmission
method
MODBUS function codes
to be used for command execution
16 bit device
WX, WY, WR, WL, DT, LD
Register
transmission
Read Coil Status (01)
Read Input Status (02)
Read Holding Registers (03)
Read Input Registers (04)
1 bit device
X, Y, R, L, DT, n, LD, n
Bit transmission
Read Coil Status (01)
Read Input Status (02)
(Note 2) Bit device L; DT, n; and LD, n cannot be specified for the header of the sender data in the partner node.
(Note 3) The No. of sent data is on a word basis for register transmission, and on a bit basis for bit transmission.
(Note 4): Devices that can be specified for D1 are: WX, WY, WR, WL, DT, LD.
(Note 5): Devices that can be specified for D2 are: WX, WY, WR, WL, DT, LD. Saved as one word in the specified area.
0: Normal completion
1: Communication port is being used for master communication
2: Communication port is being used for slave communication
3: No. of master communication commands that can be used simultaneously has been exceeded
4: Sending timeout
5: Response reception timeout
6: Received data error
6-8
To Next Page
Loading...
