Panasonic FP7 Series User Manual page 105

(Note 1) When 16-bit devices are specified for sender [S] and receiver [D2]
(Note 2) When bit devices are specified for sender [S] and receiver [D2]
■
Execution result code [D2]
Code Description
H0 Normal end
The communication port is being used in the
H1
master communication.
The communication port is being used in the
H2
slave communication.
The number of master communication
H3 instructions simultaneously used is
exceeded.
H4 Transmission timeout
H5 Response reception timeout
(Note 1) It occurs when an abnormal telegram is received. When there is a format error in the header of an
individual protocol, the communication discards the received data and a response reception timeout
occurs.
(Note 2) It occurs when the communication control I/O relays corresponding to the communication port (master
communication clear to send flag, master communication send active flag, master communication
send done result relay)are not allocated as I/O words of the CPU unit in the I/O map. It occurs only
when the number of user connections of ET-LAN is expanded and this instruction is executed
specifying the expanded connections.
■
Sample program (in the case of SCU)
● This program sends the command from the COM1 port of the CPU unit, reads the data from
the data areas DT400 to DT401 of the external device (station number 1), and writes the
data into the data registers DT100 to DT101 of the PLC.
● This program checks that the master mode is on (XC) and that sending is not in progress in
the same port (YC), and then starts up the RECV instruction.
● Using the UNITSEL instruction, specify the slot number (U0) and the COM. port number
(U1).
● In the RECV instruction, specify and execute the partner station number (U1), starting
address (DT400), data amount (U2), and PLC's starting address to store the data (DT100).
R0
DF
（ （ ） ）
R100
RECV.US
WUME-FP7COM-07
8.3 MODBUS RTU Master Communication (RECV)
XC YC
Master Master
communication communication
clear to send flag sending flag
UNITSEL
U1 DT400
S1
Code Description
H6
Reception error
H7
I/O allocation shortage error
H41 Format error
H60 Parameter error
H61 Data error
H91 Missing expansion slave unit error
execution
U0
S1
U2 DT100
S2 n D1
(Note 1)
R100
RECV execution start conditions
Clear to send flag: ON
Sending flag: OFF
RECV
Settings for the communication
port
U1
S1: Slot 0
S2：COM1
S2
RECV processing
S1: Partner unit no. (U1)
DT0
S2: Data address (DT400)
D2
n: Data amount (U2)
D1: Data storage area (DT100)
D2: Execution result code (DT0)
(Note 2)
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