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Author Topic: Pressing the reset button, or cycling the power to a chip? Which is better?  (Read 671 times)
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As the title suggests, I am curious to know which of the two is more preferable when in need of a reset. I am in a situation where it would be easier for me to cycle the power to a microcontroller, but I was wondering if it would be better for me to take a few extra steps to build in a reset button.

But, all of that aside, what is the difference between the two, and which is better for the chip?
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I doubt the chip cares in the least.

If there is any difference in the behaviour of the chip, then we as designers are in very serious trouble because the reset (which occurs in the hardware anyway on power-up) is supposed to initialise everything necessary and everything we expect for normal operation of the MCU.

Power cycling raises issues in terms of the start-up behaviour of all the other components of the system.
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Will any pins of the target be powered (be above 0.5 volts) at the moment you cycle power?
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Will any pins of the target be powered (be above 0.5 volts) at the moment you cycle power?


Yes, I do have the chip connected to an SPI bus, which generally has a positive voltage on it at all times.
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Then reset is a better choice.
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Okay. Thank you for your input. smiley
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