Mitsubishi Electronics manual Writing to file registers, Special caution when using FX1S

FX Series Programmable Controllers Devices in Detail 4

4.12.4File Registers

FX1S FX1N FX2N FX2NC

Program memory registers

File registers can be secured in the program memory (EEPROM or EPROM) in units of 500 points. These registers can be accessed with a peripheral device. While the PLC is operating, data in the file registers can be read to the general-use/ battery backed/ latched registers by using the BMOV instruction.

File registers are actually setup in the parameter area of the PLC. For every block of 500 file registers allocated and equivalent block of 500 program steps are lost.

Note: The device range for file registers in the FX1N, FX2N and FX2NC overlaps with the latched data registers. The allocation of these devices as file registers ensures that the data is kept with the program.

Writing to file registers:

• FX1S file register data can only be changed by a peripheral device such as a hand held programmer or a personal computer running the appropriate software.

For details of how to carry out the changes please reference the relevant operation manual for guidance.

•FX1N, FX2N and FX2NC file register data can also be changed by the program using the BMOV instruction.

Special caution when using FX1S:

• No file registers can be modified during RUN.

Available devices:

• Please refer to the table on page 4-33 or chapters 6 and 8, where further details of the availability of devices can be found.

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