Delta AH500 Programming Manual page 592

AH 5 00 Pr ogr am m ing Ma n ua l
Communication
timeout flag
Timeout period
Transmisson
mode
11. Timing diagrams

Mode of receiving data: K0
When data is sent, users can not cancel the sending of the data. If the conditional contact
preceding the instruction is not enable, the data will still be sent, but a completion flag will
not be set to ON after the sending of the data is complete.

Mode of receiving data: 1 or 4
Description:
① Users start/stop the execution of the instruction.
② Time in which data is sent
The period of time in which data is sent is not measured.
③ After the first character is received, the time which passes before the next character
is received will be measured. Whenever a character is received, the time measured
is cleared. The completion flag will not be set to ON until the time measured is
greater than the setting value in D
④ If the instruction is still enabled after users reset the completion flag or the
communication flag, the next communication data is sent automatically when the
instruction is scanned in the next cycle.
⑤ When the PLC begins to receive data, it begins to measure the time which passes.
The communication timeout will not be set to ON until the time measured exceeds
6 - 4 2 4
communication data.
When a timeout occurs, the PLC sets a
communication timeout flag to ON. Users have
to reset the communication timeout flag to OFF
SM104 SM105
by means of a program. After the
communication timeout is reset to OFF, the PLC
will wait for the next communication data.
If the value in SR210/SR213 is 0, the
communication timeout function will not be
SR210 SR213
enabled. The unit of measurement for time is 1
millisecond.
Choice made by COM1 between the 8-bit
processing mode and the 16-bit processing
mode
SM106 SM107
ON: 8-bit processing mode
OFF: 16-bit processing mode
+1.
2