Mitsubishi MELSEC-Q Series User Manual page 285

APPENDIX
Master station
PLC CPU
Command
G.RIFR
Device memory
App - 24
(1) Functions
(a) Operation chart for the RIFR instruction
Master module
1)
Automatic
update buffer
2)
1) Accesses the automatic update buffer specified by n1 and n2 of the
master module specified by Un.
2) Stores the data read after the device specified by (D).
(b) The RIFR instruction reads data when it is executed.
However, this instruction cannot be executed simultaneously at more than
one location for the same intelligent device station.
(c) The maximum points that can be read by the RIFR instruction are 4096.
(d) The basic number of steps of the RIFR instruction is 9 steps.
(e) The automatic update buffer assignment is performed using the "station
information settings" of the network parameters of the GX Developer.
For more details, see Section 6.2.
Specified
station
Communication
Buffer memory
commences
when
conditions
are met
MELSEC-Q
Intelligent device station
Automatic update
buffer memory
App - 24