[General] How to know crystal is in working condition

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lok

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hi all,
Iam using atmega8 for my project.After burning my program I placed it in my circuit board. But not worked properly. I think my crystal is not working.How can I check it without desoldering from my board.
 

Post your schematic here.

Check the frequency of oscillator using scope, What is the voltage present in oscillator pins.
 

You need to place a pair of capacitors in between the 2 pins of crystal and ground and by probing on oscillator pins you can check. You need to get the sine wave in any of one pin.
 
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measure the voltage at both the crystal pins. for 8051 it will have nearly half the voltage of the VCC.
 

Testing for the signal at the xtal terminals may not be good idea. Here is another thread where this has been discussed.
https://www.edaboard.com/threads/186305/
For your current problem, there may be other reasons than the xtal as well, like Vcc level, bad micro, jumper/ switch settings or others.
 



Your idea is seriously good but he want to test the crystal without removing it from the board.

It will be better if lok post his schematics to give a brief idea. Waiting for the schematic of your project
 
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There are one option called failsafe oscillator monitor. It is mandatory to use it if you want to work from external oscillator and produce relible products. MCU should start working from internal RC oscillator and then perform switching. I have no idea does this funtion realized in such old MCU, but is should be. During the switching the MCU performs cheching that external oscillator works fine and nothing bad happens.
 

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