Does crystal oscillator always oscillates?

[dann11]

Hi, I just want to ask, does the crystal always oscillates? Or for example even if the microcontroller connected to it is not working properly?

 

[Okada]

Yes, if the internal circuit of the PIC which connects to crystal is ok then it oscillates.

 

[KlausST]

Hi,

The answer surely is given in the datasheet (like so often)...for a properly working microcontroller.

But what does "not working properly" mean?
* A faulty microcontroller may do everything: not oscillate, oscillate with wrong frequency (unlikely), start/stop oscillating, properly oscillating, smoke..
* Not working because of no power: it will not oscillate
* Not working because of wrong configuration: oscillating, not oscillating
* Not working because of faulty firmware: oscillating, not oscillating, start/stop oscillating (power down and wakeup)
* ... overtemperature, overvoltage, undervoltage, reset...

Klaus

 

[FvM]

It does not oscillate if the crystal is disabled in the oscillator configuration, e.g. using internal RC oscillator, or if it's in sleep mode.

 

[Easyrider83]

Even if you will take the unsoldered component you will hear how it oscillates.