Mitsubishi Electric MELSEC-Q00U(J)CPU User Manual page 424

(3) Local device setting
(a) Setting the local device range
In the Device tab of the PLC parameter dialog box, set the range that is used as a local device.
Note that the local device range is common to all programs, and cannot be changed for each program.
For example, if a local device range is specified as M0 to M100, this range setting applies to all programs that
use the local device.
M0
M100
● The 32-bit index modification range must not overlap with the local device setting range of the index register. If
overlapped, 32-bit index modification values will be written over the local device values.
● When CPU module parameters which contain local device setting of the index register are read from a programming tool
that does not support the setting, all of the index register data will be read out as global device data.
422
Program A Program B
Local
device
Program C
Local Local
device device
Local device
range is
common to all
programs.