Precautions When Using Iowr - Omron CJ1W-C113 - REV 02-2008 Operation Manual

Writing Data with IOWR
5-4-5

Precautions when Using IOWR

IOWR is an instruction which transfers all specified data with a single execu-
tion. Therefore, it increases the cycle time for the ladder program by the time
required to transfer the data.
Refer to Appendix A Performance Characteristics for details on the times
required for transferring positioning sequences. Use them as reference values
for setting cycle time monitoring time.
When using IOWR, be sure to transfer data in complete units, and do not start
or end transfer in the middle of data. For example, with X-axis sequence #0,
the data unit consists of three words (addresses: 1000 to 1002 Hex). If the
transfer is started or ended part-way through, an IOWR format error (error
code 8701) will be generated.
When transferring the origin search high speed or the origin search proximity
speed, be sure to send both of these items together. If only one of these items
is transferred, an IOWR format error (error code 8701) will be generated.
Up to 128 words of consecutive data can be transferred with the IOWR
instruction. According to the PCU's internal processing conditions, however,
there area two possible methods with which this data is written to the respec-
tive data area within the PCU. The method that is used will be determined
automatically; it does not have to be specified in the ladder program.
Section 5-4
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