Panasonic FP7 Series Command Reference Manual page 843

● After it is confirmed that connection 1 is established in master mode (X90) and no
transmissions are currently being executed for the same port (Y90), the RECV instruction is
started.
● The UNITSEL instruction is used to specify a slot number (LAN port: U100) and the
connection number (U1).
● In the RECV instruction, specify and execute the type of MODBUS command and partner
station number (H0301), starting address (H0), data amount (U2), and PLC's starting
address to store the data (DT100). Check addresses of connected devices in the instruction
manuals of devices.
R0
DF
（ （ ） ）
R100
RECV.US
■
Time chart (in the case of CPU with built-in ET-LAN)
Master communication
clear to send flag
(X90 - X9F)
Master communication
sending flag
(Y90 - Y9F)
Execute RECV
Master communication
sent flag
(Y70 - Y7F)
Sending data
Response reception
processing
■
I/O allocation (in the case of CPU with built-in ET-LAN)
I/O number
Master communication
X90 to X9F
clear to send flag
Master communication
Y90 to Y9F
sending flag
WUME-FP7CPUPGR-12
15.7 RECV (MODBUS Master: Function Code Specification)
X90 Y90
Master Master
communication communication
clear to send flag sending flag
UNITSEL
H301
S1
Check that the
flag is ON
Check that the
flag is OFF
Name
execution
U100
S1
H0 U2 DT100
S2 n D1
Turns ON when a connection is established in the master
communication.
Turns ON during sending data based on the SEND/RECV
instruction.
Turns OFF when the ED instruction is executed after the
completion of the response receive processing.
R100
RECV execution start conditions
Clear to send flag: ON
Sending flag: OFF
RECV
Settings for the communication
port
U1
S1: CPU LAN port (U100)
S2: Connection 1 (U1)
S2
RECV instruction execution
S1: MODBUS command (H03)
DT0
Partner station no. (H01)
D2
S2: Data address (H0)
n: Data amount (U2)
D1: Data storage area (DT100)
D2: Execution result code (DT0)
RECV instruction executable
conditions
Clear to send flag (X90 - X9F): ON
Sending flag (Y90 - Y9F): OFF
Sending flag (Y90 - Y9F):
While sending: ON
ED instruction executed following
response reception processing: OFF
Sent flag (Y70 - Y7F):
Normal completion: OFF
Abnormal completion: ON
Description
15-49