Panasonic FP7 Series User Manual page 160

9.4 Receiving Operation
● When data are received, the received flag (X70 to X7F) turns ON.
● When the GPRECV instruction is executed, data are copied to the specified area, and the
received flags (X70 to X7F) are turned OFF. The received flags (X70 to X7F) are turned OFF
when I/O refresh is executed at the start of the following scans.
Receive buffer
Received data
Reception done
flag (X70 - X7F)
Execute GPRECV
■
I/O allocation (in the case of CPU with built-in ET-LAN)
I/O allocations
X70 to X7F
■
Precautions during programming (in the case of CPU with built-in ET-LAN)
● Use the UNITSEL instruction immediately before the GPRECV instruction to specify a target
connection for communication.
● When the general-purpose communication received flag is ON for the targeted connection,
execute GPRECV.
● The maximum volume of data that can be received in one session using the GPRECV
instruction, from the LAN port of the FP7 CPU unit, is 16,384 bytes.
● Depending on the communication format of an external device, if a header and a terminator
are contained, they are stored in the operation memory as part of receive data. When
necessary, insert a program to extract data content.
● In the case of a direct address and an index modification address, specify the same device
for D1 and D2. At the same time, specify the addresses so that D1 is less than D2.
● As the communication cassette (Ethernet type) has an Ethernet-serial conversion function, the
internal interface operates with similar programs as the case of SCU. The setting method and
programming method are different from those for the CPU with built-in ET-LAN. Refer to the
section describing the case of SCU.
■
Flag operations
Name
SR7
SR8
(ER)
9-26
Name
General-purpose
communication received
flag
Description
To be set in the case of out-of-range in indirect access (index modification).
To be set when the destination range is outside the accessible range.
An SCU or ET-LAN unit does not exist in the slot specified by UNITSEL.
The communication mode of the communication port specified with UNITSEL is not
"General-purpose communication".
The COM port specified by UNITSEL does not exist.
Reception done flag (X70 - X7F):
Reception done: ON,
Received data copy done using
GPRECV instruction: OFF
Turns ON when receiving is completed in the general-
purpose communication mode.
Description
WUME-FP7COM-07