i ordered some signal generator but i let it fall and maybe i supplied wrong voltage accidentally idk

how am i supposed to test wich component is dead
ic chip atmega16A and 16 mghz crystal ocillator
when i measure over oscillator i measure 0.8 V dc
the ic chip used to control some lcd screen also wich doesnt work anymore either

can somebody help me ?

 

some signal generator

?

 

i mean function generator used to make square sine... waves

 

Photo?
Schematic?
Visible damage?

 

Answering with the same level of information that you have (NOT) provided. You will have probably destroyed one or more components. Replace those components.

Les.

 

if you did reverse the voltage - it might be unfixable by simple means . . . depending on the circuit

 

no visual damage

 

I don't think dropping it would damage anything that would not be visible. The thing is small and light. Are all the jumpers still in the right places? If you maybe accidentally applied the wrong voltage to it, how much voltage might that have been? The ATmega processor chips are very susceptible to over voltage. If that is blown, you may as well scrap it.

 

ow that could be it the cables were pretty lose and wiggly so it could have been connected to 12V or -12V

could only the atmega die from this ?

 

If in post #9 when you wrote "it" you were meaning the VCC rail (Which should be + 5 volts) then applying + 12 volts or - 12 volts to the VCC rail then I think the ATMega will have been destroyed.

Les.

 

ow ok could that have destroyed the lcd screen or oscillator ?

 

Yes. Or both.

 

The oscillator is in the ATMega and the crystal should be OK.

 

the "LCD screen" is usually driver and the LCD-screen -- the last of which is "destroyed" from applying several seconds DC to LCD segments ... e.g. in case the accidental false power on the LCD itself likely survived . . . other is the driver (but you likely can test it out if you send some initalization data to it by anything suitable for such)