MITSUBISHI ELECTRIC QJ71C24N - Manual (Page 328)

App. - 34 App. - 34
MELSEC-Q
APPENDIX
Appendix 9.2 When accessing buffer memory using sequence program
In the following program example, data are read from or written to the buffer memory of
the Q series C24 using the REMFR/REMTO instruction.
POINT
Use GX Configurator-SC to change the default value of the buffer memory. Using
GX Configurator-SC, save the new setting value to the flash ROM of the Q series
C24. (Refer to Chapter 8.)
(1) Program conditions
The following program reads data from or writes data to the QJ71C24N buffer
memory (CH1 side word/byte units designation area) when the read/write
command (X1020, X1021) turns ON.
(a) Devices used
:
• Read/write command.............................................................. X1020, X1021
• Read/write command pulse signal ......................................... M10, M11
• Completion device for REMFR/REMTO instruction .............. M100 to 103
• Normal/abnormal completion flag for REMFR/REMTO
instruction................................................................................ M200 to 203
• Read from word/byte units designation area ......................... D0
• Write to word/byte units designation area.............................. D1
(2) Program examples
(a) Read from buffer memory
Changes the read command
into pulses.
Abnormal completion of
REMFR instruction
Normal completion of
REMFR instruction
Reads the word/byte units
designation area data of the
buffer memory to D0.
(b) Write to buffer memory
Abnormal completion of
REMTO instruction
Changes the write command
into pulses.
Sets the word/byte units
designation to byte.
Transfers the setting value to
the word/byte units designation
area of the buffer memory.
Normal completion of
REMTO instruction