[PIC] What happened to my PIC?

[gusts]

Hello all!

I just made a mistake by configuring RB0/INT as output (PIC16F84A) and applied +5 V to this pin? Could it be true that the whole microcontroller was damaged? Now I am unable to execute the most simple program (setting all pins to output +5 (V)).

Thanks and best regards
gusts

 

[ADGAN]

Check the datasheet, if your PIC supports up to 5V or 5.5V, I'm guessing it has not damaged. Try some simpler program like lighting a LED. Check whether you have provide 5V via a resistor to the first pin, oscillator with caps, Vdd - 5V and Vss - 0V.

 

[wp100]

Hello all!

I just made a mistake by configuring RB0/INT as output (PIC16F84A) and applied +5 V to this pin? Could it be true that the whole microcontroller was damaged? Now I am unable to execute the most simple program (setting all pins to output +5 (V)).

Thanks and best regards
gusts

Hi,

Its always 50/50 if you have damaged the port RB0 , the whole Chip or nothing at all.

If your program does not seem to work, try putting the chip in your programer and see it you can Read the program out of it.
If so, reprogram the chip with a simple test program to flash every pin on and off for a second or two and then check each pin with a led and resistor or your test meter.

 

[gusts]

Thanks to all!
I bought new PIC16F84A but it turned out there was nothing wrong with the previous one. Could it be true indeed that all I had to do was pulling /MCLR pin to Vdd through R?
Best regards
gusts

 

[wp100]

Thanks to all!
I bought new PIC16F84A but it turned out there was nothing wrong with the previous one. Could it be true indeed that all I had to do was pulling /MCLR pin to Vdd through R?
Best regards
gusts

Hi,

Many of the older 16F chips like the 84A will only work if pin1 / Mclre is pulled up to +5v , either by a direct wire or something like a 10k resistor.

With a Pull up resistor fitted, if you add a switch from Pin1 to 0v then that will act as a hardware Reset switch that starts you program off from the beginning again.