Omron CJ1W-C113 - REV 02-2008, Руководство по эксплуатации

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Reading Data with IORD Section 5-5
5-5-5 Flags
When data is transferred using IORD, the Error Flag (word n+8, bit 12), the
ER Flag and the Equals Flag can be used to check whether the transfer has
been completed successfully. If the Error Flag (word n+8, bit 12) is ON, an
error code will be output to n+10 in the operating memory area. Check this
error code to determine the cause of the error and correct it.
Flag ON Condition OFF Condition
ER • The number of transfer words set
in W is outside the range 0001 to
0080 Hex.
• The unit number set in W is out-
side the range 0000 to 005F Hex.
• A Special I/O Unit that is not com-
patible with the IORD instruction
has been specified.
• A Special I/O Unit for which a set-
ting error has been made or an
error is being generated has been
specified.
Anything else.
= The transfer has been completed
without error. • The address set in C, or the area
specified with this address and
the number of transfer words set-
ting, corresponds to only some,
and not all, of the words used to
store an item of data. For exam-
ple, the Equals Flag would turn
ON if the destination address set
for a speed, which is stored in 2
words, was set to an address that
corresponded to only the second
word.
• The address set in C, or the area
specified with this address and
the number of transfer words set-
ting, is outside the range of PCU
addresses.
• The number of transfer words is
set to 0.
• Another write process is being
executed.
• Data is being saved to flash
memory.
(Data is being saved for a SAVE
DATA bit or data is being saved
from the CX-Position.)
• The has just been turned ON or
restarted and is still performing
initial processing.