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cannot get 4Mhz frequency for PIC16F84A

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New Member
hi i'm having troubles generating 4Mhz frequency for my PIC16F84A.
I'm using an XTAL crystal oscillator 4Mhz connected to pin 16 together with two 22pf capacitors connected to the each legs of the crystal oscillator
Pin 15 is also connected to pin 16 and to one of the capacitors.
both capacitors are grounded. I'm implementing it on breadboard.
I cannot seem to get the intended frequency. what is wrong??
should i mention anything regarding the xtal crystal osc in my program??
my program is intended initially for pic16f84 but it assembles okay for this pic. help me plss......how can i make my crystal osc function??


New Member
If I understand you correctly you are connecting the XTAL incorrectly.
You should have one pin of the crystal on pin 16 and the other on pin 15.
The caps should go from pin 16 to ground and from 15 to ground.



New Member
if i wanted to view the waveform generated where do i place the probe??
pin 16 or pin 15 ? is the from goin into pin 16 the same as the waveform generated at pin 15??

does any one have suggestions on the values of resistor and capacitor that i can use to from an rc oscillator for the pic16f84a? what type of connections should i make to obtain a 4MHz frequency? will it differ from the crystal osc??
i am greatful for any advices submitted, :wink:
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