trouble programming PIC16F627A with PICKit 3

T

theBob_

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Trouble with PICKit 3 and PIC16F627A. I can't get this chip to program at all. Running MPLAB X v6.20 and powering the target with a steady 5V.
I keep getting an error saying the received hex code doesn't match the expected
I tried a second chip and even a second programmer, but no luck
could it be a config bit issue or just bad code I grabbed online?
Any ideas how to fix this?
 
Had the same thing happen with a 16F ages ago. Turns out it was set to use an external clock which is why it wouldn't check out. You should check the oscillator and code protection bits. Try wiping it clean before you program it
 
Without knowing the details, that error usually means there's something up with the config bits or Vpp timing.
Just be sure MPLAB actually has the settings for PIC16F627A turned on, turn off LVP, and just make sure MCLR isn’t stuck on low when you're programming.
 
I literally just dealt with this problem last month. The code I got online had protection bits turned on, so it kept failing the check. I wiped all the config bits, erased the whole chip, and then re-programmed it. Finally worked.
 
I’d bet money it’s LVP. If that bit is enabled in your config but your hardware isn't pulling the PGM pin correctly, the PICKit will fail every time. Disable LVP in your code first
 
That LVP setting can really catch you off guard if the hardware isn’t configured properly.
 

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