Buffer Memory; How To Read/Write From/To Buffer Memory; Direct Specification Of Buffer Memory - Mitsubishi Electric MELSEC-F Series User Manual

FX -1PG User's Manual
3U
7.

Buffer Memory

The FX -1PG positioning parameter, control data, and monitor data are read/written from/to the PLC via the
3U
buffer memory (BFM).
When the FX
3U
when the power supply is turned on.
The buffer memory is mainly classified into the following three types.
• Positioning parameters (BFM#0 to #15, #32 to #52)
The positioning parameters to set speed and units of measurement.
• Control data (BFM#16 to #25, #53 to #57)
The control data is user-specified data for controlling the positioning control.
• Monitor data (BFM#26 to #30, #58 to #62)
Operating conditions for the positioning control are stored as monitor data.
Caution
The instruction data format (FROM/TO, DFROM/DTO, etc.) must match the target BFM's data format. When
the instruction data format does not match the target BFM's data format (16-bit/32-bit), the FX
read/write data to the BFM properly, and no error will appear. This may cause an operation error for
positioning.
7.1

How to Read/Write from/to Buffer Memory

To read/write from/to buffer memory in the FX
that directly specify the buffer memory. For details on the other methods, refer to the following Manual.
7.1.1

Direct specification of buffer memory

When directly specifying the buffer memory, specify the following device in the source or destination area of
the applied instruction as follows:
Unit No. (0 to 7)
1. Reading out BFM data to PLC (MOV instruction)
If the following program is created, 1 point of data will be read out from the buffer memory BFM#30 of unit No. 1
to data register D10.
Read command
Buffer memory No.
2. Writing PLC data into BFM (MOV instruction)
If the following program is created, 1 point of data (K4000) will be written to buffer memory BFM#0 of unit No. 1.
Write command
Transfer source
50
-1PG power supply is off, the buffer memory data is cleared, and initial values are written
Buffer memory No. (0 to 32766)
FNC 12
U1\G30
MOV
Unit No.
FNC 12
MOV
-1PG, use the FROM/TO instructions or applied instructions
3U
is substituted with a number
D10
K4000 U1\G0
7.1 How to Read/Write from/to Buffer Memory
→ For details, refer to Section 7.3.
→ For details, refer to Section 7.4.
→ For details, refer to Section 7.5.
→ Refer to Programming manual.
Transfer result
Buffer memory No.
Unit No.
7 Buffer Memory
-1PG will not
3U