Panasonic FP7 CPU Unit - Operation of General-Purpose Communication; Read Data from an External Device; Write Data into an External Device

General-Purpose Communication
7.1 Operation of General-Purpose Communication
7.1.1 Read Data from an External Device
 Read data from a partner device
In general-purpose communication, communication is executed by sending commands that
suit the partner device, and receiving responses. Command messages are sent by
formulating a data table for message in accordance with the protocol, on the given data
register, and subsequently executing GPSEND command.
External device
ABCDE
1 2 3 4 5
Command message
Response message
D CDT102
・・EDT103
B A
DT101
U 5DT100
H ・・・35
00003
・・・・・・・・
・・・・・・
H 34 3300002
H 32 3100001
PLC
Specify and read address based on GPSEND/GPRECV command
Note: The above figure indicates the data part. In communication
via LAN, a header including size information of the sent data is added.
7.1.2 Write Data into an External Device
 Write data into a partner device
In general-purpose communication, communication is executed by sending commands that
suit the partner device, and receiving responses. Command messages are sent by
formulating a data table for message in accordance with the protocol, on the given data
register, and subsequently executing GPSEND command.
External device
ABCD 1 2
XYZ
Command message
Response message
D CDT102
32 31DT103
B ADT101
U 6DT100
・・・・・・・・
00003
・・・・・・・・・・・・・・
・・・・・・・・
00002
32 3100001
PLC
Specify and write address based on GPSEND/GPRECV command
Note: The above figure indicates the data part. In communication via LAN, a header including size information of the sent data is added.
KEY POINTS
• There is no relevance between the operation of transmission by GPSEND
command and the operation of reception by GPRECV command.
7-2