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Circuit – FUJITSU F2MCTM-16LX User Manual

Page 395

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CHAPTER 19 LOW VOLTAGE DETECTION/CPU OPERATING DETECTION RESET

19.5

Notes on Using Low Voltage/CPU Operating Detection
Reset Circuit

This section explains the note on using the low voltage/CPU operating detection reset
circuit.

Notes on Using Low Voltage Detection Reset Circuit

Disabled operating stop from program

The low voltage detection reset circuit operates continuously after the power supply is turned on and the

operating stabilization wait time passes. Operating can not be stopped with software.

Operating at STOP mode

Low voltage detection reset keeps operating at the STOP mode. Therefore, if a low voltage is detected in

the STOP mode, reset is generated and the STOP mode is canceled.

Notes on Using CPU Operating Detection Reset Circuit

Disabled operating stop from program

CPU operating detection reset circuit operates continuously after turning on the power supply. Operating

cannot be stopped with software.

Reset generation control of CPU operating detecting function

CPU operating detecting function should clear the counter at regular intervals. The counter is cleared by

writing "0" to the CL bit of the LVRC register, and the reset generation can be controlled.

Stop and clear of counter

In the mode CPU stops operating, CPU operating detecting function clears the counter and stops operating.

Operation in sub-oscillation mode

The CPU operation detection function will stop operation in sub-oscillation mode. For this reason, also use

the watchdog reset function.