Supplementary Setting - Mitsubishi Electric QJ71GF11-T2 User Manual

(c) Supplementary Setting
[CC IE Field Configuration]
Item

Supplementary Setting

[Supplementary Setting]
Description
Set "Link Scan Mode Setting", "Loopback Function Setting", "Block
Data Assurance per Station", and "Operation Setting for Returning".
(1) Link Scan Mode Setting
Item
Link scan is performed asynchronously with the
sequence scan of the CPU module. Select this item to
Asynchronous shorten input transmission delay time when sequence
scan takes much time than link scan. Note that output
transmission delay time will become longer.
Cyclic transmission is performed punctually. Link scan
time will be the constant link scan time set in this
setting.
However, when the actual link scan time is longer than
the specified link scan time, cyclic transmission is
Constant Scan performed by actual link scan time.
While constant link scan is used to keep link scan time
constant, the transmission delay time is not kept
constant by this function. To keep transmission delay
time constant, select "Synchronous".
Link scan is performed synchronously with the
sequence scan of the CPU module. Select this item in
the following cases:
To shorten output transmission delay time (Note that
when sequence scan takes much time than link scan,
input transmission delay time will become longer.)
Synchronous
To keep transmission delay time constant
When a link scan is synchronized with a sequence
scan, modify the program so that the sequence scan
time of the CPU module will be within 200ms. If
200ms is exceeded, slave stations may be
disconnected.
*1 The sequence scan must be constant as well.
Set a time value under "Constant Scanning" in
the "PLC RAS" tab of the PLC parameter
window.
CHAPTER 7 PARAMETER SETTING
Description
*1
Setting range
• Link Scan Mode Setting:
Asynchronous, Synchronous
(Default: Asynchronous)
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