Writing/Reading Device Data To/From Standard Rom - Mitsubishi Electric MELSEC-Q00U(J)CPU User Manual

3.30

Writing/Reading Device Data to/from Standard ROM

This function writes device data to the standard ROM. Writing the fixed values for operation and operation results to
the standard ROM can prevent losing data due to low battery. Also, timing of writing to the standard ROM can be set by
an instruction.
(1) Execution method
Device data are written to the standard ROM by the SP.DEVST instruction.
The device data written to the standard ROM is read to the specified device by the S(P).DEVLD instruction.
(2) Devices that can be written to the standard ROM
The following table lists the devices whose data can be written to the standard ROM.
X, Y, M, L, B, F, V, T, ST, C, D
*1 The extended data register (D) is included.
*2 The extended link register (W) is included.
(3) Setting method
The area for storing the device data is set in the standard ROM by the PLC file tab of the PLC parameter dialog
box.
Set a file size
(A file name is fixed to DEVSTORE).
(a) File size setting
The capacity that can be set varies depending on the CPU module.
Q00UJCPU, Q00UCPU, Q01UCPU
Q02UCPU
QnUD(H)CPU, Built-in Ethernet port QCPU
Remark
For details of the instructions, refer to the following.
MELSEC-Q/L Programming Manual (Common Instruction)
258
Device
*1 *2
, W , SM, SD, SB, SW, R, ZR
CPU module
Storage location
Standard ROM (device data storage location)
Setting range
1K Points (fixed)
1 to 16K Points
1 to 512K Points