Search found 46 matches

Guys, it works now, it's official, the other PIC's are dead. I finally was able to make the blinker work and now I got back to the original thing with the 74LS48 and it's working, thanks for all your ...

Thank you all for your feedback, I'm sorry I couldn't interact with you earlier.

Today I got three fresh new PIC16F877A and 10 fresh new 4Mhz crystals (It was a pack, I wish I could have found a sm ...

I just realized that if I unplug GND from my PIC, the led stays on which makes me believe that somehow the pic is just shorting B0 to VDD because, if I'm not wrong, it wouldn't run without GND connect ...

PCM programmer, I rechecked all the connections and I realized I had the PIC displaced one pin, now it is properly placed on my bread board and the led lights on but wont blink, just stays on. I tried ...

It looks like there are black wires going to Vdd and Vss on pins 11&12.
Is it possible both of those are ground rather than 5V and Gnd?

I must admit that my choice of colors is not the most ...

I did check between VDD and GND and my meter shows about 4.8v (approx) I guess that i wouldn't matter those 0.2v down that I have...

I'm afraid I only have 3 PIC16F877A (one of em seems to be dead ...

I just tried connecting the led to the B0 pin with a 330 ohm resistor and using the code provided and I'm afraid it still doesn't work.

I'm starting to consider that my PIC is just dead, the weird ...

PCM programmer you are right, I use a PICkit 3 clone with a Zif socket to program my pic, and I use it on standalone mode so I use the PICkit 3 Programmer app instead of MPLAB.

I will make the ch ...

Post your LED blinking program.

If possible, post a link to a photo of your test board. It should be
a close-up photo so we can see all the connections.

Answering to your request, here is a ...

Your PIC may not even be running. Setup a circuit it blink an LED
at 1 Hz.

You are right, I tried to do a simple led blinking via B7 and doesn't do a thing, checked my connections, I wonder if my ...

PCM programmer I just did what you suggested and as I was expecting it didn't change a thing, I mean, it still doesn't work, and it seems to be related to the fact that the 2v I'm getting on the INPUT ...

Do you have an 8 MHz crystal and two 20pf ceramic capacitors
installed for the crystal circuit ?

Do you have a 10K resistor between the MCLR pin and +5v ?

Also change your first 3 lines to thi ...

Thanks for the info newguy, I placed a 0.1uF (104) ceramic cap between VCC and GND pins on my 74LS48, and I also added some 10K pullups on BI, BO, and LT pins.

All that being said I'm facing exactl ...

I assume we are talking about a "regular" electrolytic cap, aren't we?? like a 0.1uF that goes between GND and VCC?

Is it normal that I get almost 2V output at A, B, C, D???

and before ...

On the circuit design I provided I didn't wire those pins because, first you don't need to connect the PIC to either vcc, gnd or even the crystal on Proteus, by on my fisical circuit I do have all tho ...