Omron CJ2 - 02-2010 User Manual page 172

5 Understanding Programming
FIORF(225): SPECIAL I/O UNIT I/O REFRESH
FIORF(225) can be used to refresh the following data in a Special I/O Unit with the specified unit
number, only when necessary.
FIORF
N
Example:
FIORF
&20
A Special I/O Unit's regular cyclic I/O refreshing can be disabled in the PLC Setup (by turning ON
the Unit's Special I/O Unit Cyclic Refresh Disable Bit), and I/O refreshing can be performed with the
Unit only when necessary by executing FIORF(225). This function can prevent the PLC's cycle time
from increasing when a Special I/O Unit is connected in the PLC.
Using DLNK(226): CPU Bus Unit I/O Refresh
DLNK(226) can be used to increase the refresh frequency for words allocated to a CPU Bus Unit in
the CIO Area and DM Area, and for data that is specific to the CPU Bus Unit.
*1 Data specific to a CPU Bus Unit would include data links for Controller Link Unit or SYSMAC LINK Units, as
well as remote I/O for DeviceNet Units.
DLNK
N
Example:
DLNK
#1
Application Example: With a long cycle time, the refresh interval for Controller Link data links can
5-82
N: Special I/O Unit's unit number
Refreshes the CIO words and DM words allocated to
the Special I/O Unit with unit number &20.
N: Unit number of CPU Bus Unit
The instruction on the left would refresh
the words allocated to the Unit in the CIO
Area and DM Area, and data specific to
*1
the CPU Bus Unit with unit number 1.
*1 If the CPU Bus Unit with unit number
1 is a Controller Link Unit, data links
are refreshed.
be very long. This interval can be shortened by executing DLNK(226) for the
Controller Link Unit to increase the frequency of data link refreshing.
*1
CJ2 CPU Unit Software User's Manual