What is the function of the reset circuit outside the microcontroller when the microcontroller is reset due to a watchdog timeout?

一沙一世

What is the function of the reset circuit outside the microcontroller when the microcontroller is reset due to a watchdog timeout? [Copy link]

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What is the function of the reset circuit around the microcontroller when the microcontroller is reset due to a watchdog timeout?

wangerxian

Watchdog reset is a software reset, and peripheral reset circuit is a hardware reset. There is no connection between the two.

maychang

[What is the function of the reset circuit of the microcontroller peripheral when the microcontroller is reset due to a watchdog timeout? ]

When the watchdog is reset, the peripheral reset circuit does not work.

一沙一世

wangerxian posted on 2023-2-10 09:35 The watchdog reset is a software reset, and the peripheral reset circuit is a hardware reset. There is no connection between the two.

Thank you. I heard from a former colleague that if the voltage waveform generated by the reset circuit is not steep enough when the peripheral reset potential is powered on, the microcontroller will not work properly. Is this problem true?

一沙一世

maychang published on 2023-2-10 09:44 [What is the function of the reset circuit of the microcontroller peripheral when the microcontroller is reset due to the watchdog timeout? ] When the watchdog is reset, ...

Thank you. I heard from a former colleague that if the voltage waveform generated by the reset circuit is not steep enough when the peripheral reset potential is powered on, the microcontroller will not work properly. Is this problem true?

maychang

Yishayishi published on 2023-2-10 10:05 Thank you. I heard from a former colleague that if the peripheral reset potential is not enough when the reset circuit generates a voltage waveform when powered on...

When the watchdog is reset, the peripheral reset circuit does not operate, so there is no problem of "the voltage waveform generated by the reset circuit is not steep enough".

When the peripheral reset circuit generates a reset, the watchdog does not operate, so the reset of the peripheral reset circuit has nothing to do with the watchdog.

freebsder

Reset failed?

chunyang

That depends on what kind of external reset circuit it is. Generally speaking, external reset circuits are power-on or power monitoring reset circuits, which have nothing to do with watchdogs. In some cases, there are external watchdogs or special conditional reset circuits, which require specific analysis.

wangerxian

Yishayishi published on 2023-2-10 10:05 Thank you. I heard from a former colleague that if the peripheral reset potential is not enough when the reset circuit generates a voltage waveform when powered on...

It should be too steep, which will cause the microcontroller to malfunction after reset. . .

cheery60

You should understand the principle of the peripheral reset circuit. The peripheral reset circuit belongs to hardware reset. The reset condition of the microcontroller is that the reset pin keeps low level (some models are high level) for a period of time before it resets. Therefore, the peripheral reset circuit generally uses a resistor-capacitor charging circuit as the reset circuit. At the moment of power-on, the voltage across the capacitor cannot change suddenly, so it is low level, the microcontroller is reset, charged to high level, and the microcontroller keeps working normally. The watchdog reset has no effect on the peripheral reset circuit.

starcat123

Yishayishi published on 2023-2-10 10:05 Thank you. I heard from a former colleague that if the peripheral reset potential is not enough when the reset circuit generates a voltage waveform when powered on...

Isn't NRST just a question of low level duration?

If you say "not steep enough", then change the resistor/capacitor value (actually the low level time), will it work?