trouble with my 16f84a

[mackrackit]

I looked at the melabs datasheet and it says that I do not have analog pins. I'm not go to dismiss the possibility that I misunderstood though

My mistake, dirty glasses

I would say try a better power supply. Is there a way to pull power from the EPIC?

[cavity creep]

Not that I know of.At least I don't think so. I tried another power supply(some aa's) , but to no avail. I'm wondering if the programmer is not setting the pin high as intstructed. Could this be a problem with the EPIC or perhaps a bad cable? Is there any way to test the programmer(or the chips for that matter) for a defect?
If anyone needs me, I'll be staring blankly at this breadboard with with contempt.
Thanks,
Shawn

[Acetronics2]

Hi, Shawn

Did you also think to tie the MCLR pin to V+ ???

some details about Hardware are not too much nor ... YOUR scheme will be perfect.

...

Alain

[cavity creep]

Hi Alain. Yes it's definitely tied to positive.I'm actually getting power throughout the chip, only little or no power to the portb pins for some reason.
I was wondering if this was an intermittent kind of problem initially, because I would get at least one LED to blink and then none at all.But two different PICs with the same problem? Also different power supplies seem to be ineffective.

As far as the circuit goes, I can't find a diagram right now to post(about to head out for the afternoon), but I'll try to give you a breakdown.

pin 4= POSITIVE with 47k resistor

pin 5= NEGATIVE

PIN 6 AND 7= LEDs with 470 ohm resistors(and yes, the polarity is correct)

pin 14 =positive

pin 15 and 16 =crystal with two 22 pf caps attached to ground

If you see something I've done wrong, please feel free to let me know.Frankly I'm baffled.

[Bruce]

Does this work?

P_Val VAR BYTE
TRISB=0

start:
  P_VAL=2  ' RB0=0, RB1=1
  portb = P_VAL
  pause 500
  P_VAL=1 ' RB0=1, RB1=0
  portb = P_VAL
  pause 500
  goto start

[aratti]

pin 4= POSITIVE with 47k resistor

pin 5= NEGATIVE

PIN 6 AND 7= LEDs with 470 ohm resistors(and yes, the polarity is correct)

pin 14 =positive

pin 15 and 16 =crystal with two 22 pf caps attached to ground

I have never seen a 47K resistor on reset pin! Tray a 10K

Pin 5 negative? , surely you mean ground !

crystal with two 22 pf caps attached to ground (4 MHz?)

In your program modify pause to 5000, then with a DVM measure port pins. If you see both pins turning on & off then you have a bad ground or a bad resistor or a bad led connected to the led that doesn't work. On the other hand if you don't see the +5 volts ont both pins than you have a bad pic.

Appart from that I don't see reason for your leds not blinking.

Al.

[Acetronics2]

Hi, Shawn

Could you post your HEX code ( not Basic ! ) ???

I think it's the only way to verify what you put into your Pic ... ( Mr de la Pallice dixit )

Alain

[cavity creep]

I have never seen a 47K resistor on reset pin! Tray a 10K

Pin 5 negative? , surely you mean ground !

crystal with two 22 pf caps attached to ground (4 MHz?)

In your program modify pause to 5000, then with a DVM measure port pins. If you see both pins turning on & off then you have a bad ground or a bad resistor or a bad led connected to the led that doesn't work. On the other hand if you don't see the +5 volts ont both pins than you have a bad pic.

Appart from that I don't see reason for your leds not blinking.

Al.

For this particular PIC at least , it seems to be the norm to use a 47k resistor. The crystal is 4 mhz. And yes,I meant ground:P
I tried what you recommended , and checked the pins.I am getting a very tiny voltage value ( the last was 35.6 mV.).I've got a feeling I have a couple of bad chips, unless someone can think of another reason for this

Alain I'm going to post the Hex listing here of the most recent wink program.Thanks for taking a look at it.

:1000000028288F018E00FF308E07031C8F07031CEA
:10001000232803308D00DF300F2003288D01E83EB8
:100020008C008D09FC30031C18288C070318152838
:100030008C0764008D0F15280C181E288C1C222894
:1000400000002228080083130313831264000800B1
:1000500006148316061083128610831686108312E8
:1000600013308F008830022006108316061083128A
:10007000861483168610831213308F008830022076
:060080002828630041285E
:02400E00FD3F74
:00000001FF