Omron SYSMAC C200HW-PCS01-EV1, Руководство по эксплуатации

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10-2-3 Socket Services and Socket Status
When using socket services, it is important to consider the timing of the status
changes in the socket status area. The diagram below shows a program flow-
chart for opening UDP.
Program flow is similar for other socket services. Replace the names of the
appropriate flags in the flowchart to adapt it to other socket services.
An error occurred. The PC Card
Unit did not receive the UDP
OPEN REQUEST command.
Check socket status.
Start UDP Open
OFF?
OFF
The specified UDP socket is
already open.
Program Flow
Is Bit 15 (Open Flag) in the socket status word for
the socket being used OFF?
(Checks to see if the socket is open before com-
munications and close processing.)
YES
Error Evaluation
Check the Instruction Enabled Flag.
Execute FINS command (via CMCR) for PC Card Unit.
Check response.
Check Opening Flag status.
Check results storage area response code.
ON?
The specified port is running
network communications.
Is the appropriate bit in word 252 for the operating
level being used ON?
YES
Use the CMCR to send the UDP OPEN REQUEST com-
mand (2701) to the PC Card Unit.
Is the response code = 0000 (normal) for the
UDP OPEN REQUEST command?
Wait until bit 00 in the socket status turns OFF
(open complete).
Is response code = 0000?
0000?
YES
0000?
YES
UDP opened
(Socket status bit 00)
An error occurred. The specified
socket could not be opened.
NO
NO
NO
NO
Using Socket Services
Section 10-2