I/O Refresh Instructions; Rfs, Rfsp; I/O Refresh - Mitsubishi MELSEC-Q/L Programming Manual

6.7

I/O Refresh Instructions

6.7.1

RFS, RFSP

I/O refresh

6.7.1
RFS, RFSP
RFS
RFSP
: Head number of the devices to be refreshed (bits)
S
n : Number of refreshes (BIN 16 bits)
Setting Internal Devices
Data
Bit Word
S
(Only X, Y)
n
Function
(1) Refreshes only the device being scanned during a scan, and functions to fetch input from external sources or to output
data to an output module.
(2) Fetching of input from or sending output to an external source is conducted in batch only after the execution of the END
instruction, so it is not possible to output a pulse signal to an outside source during the execution of a scan.
When the I/O refresh instruction is executed, the inputs (X) or outputs (Y) of the corresponding device numbers are
refreshed forcibly midway through program execution. Therefore, a pulse signal can be output to an external source
during a scan.
(3) Use direct access inputs (DX) or direct access outputs (DY) to refresh inputs (X) or outputs (Y) in 1-point units.
[Program based on the RFS instruction]
Command
X0
Command
[Program based on direct access input and direct access output]
DX0
Direct access input
Command
Command
J \
R, ZR
Bit Word
RFS X0
K1 Refreshes X0
Y20
RFS Y20 K1 Refreshes Y20
DY20
Direct access output
High
Basic
Process
performance
RFS S
RFSP S
Zn
U \G
––
RFS, RFSP
LCPU
Redundant Universal
n
n
Constants
Other
K, H
––
––
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