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PIC Burner weird problem


GordTheRogue
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Hello to all. First of all i would like to tell the moderators that if needed they can "cut&paste" this post into the previuos PicBurner related post.

My story started with failure on programming the bootloader with a Willem PCB5.0 burner. Thereafter i decided to build the PICBurner module, i had all the components so i etched the PCB without the ground copper layer because i didn't found it into the PCB Eagle's file (surelly my fault).

I soldered all the stuff, grounding with cables. There's only a difference from the original, i used TO220 size for the LM317 and the 7805 voltage regulators, i checked the pinout on the Web all seems fine.

The first test was bad, i burned a 74HC14 (wrong orientation), but the voltage testing passed, i'm using a DC 15v supply.

I tried with other 74HC14 but:

1) Power's Green LED went on (OK)

2) Vdd's Yellow LED went on when LPT printer port is connected to the PICBurner (BAD) (LPT pins are right)

3) P18 did not see the PICburner but LPT port test (100k resistor) passed (BAD)

So i checked the schematic and the PCB board, i forgot two ground pins, the R12 and the 7pin of the 74HC14. After soldering, i tested again and:

1) Power's Green LED stays OFF (BAD)

2) 7805 voltage regulator goes really really hot! (BAD)

How could it possible that the 7805 goes so hot after putting the ground at those pins?

Again sorry for my bad english, ask if you need more info. Thanks to all, you out there are very kind!

Gord The Rogue

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hello,

I don't actually know how to solve your problem, but my advice is:

1-Use a multimeter to check what voltage your getting from your dc power supply;

2-Check how many Amps your DC is outputting (I'm not really sure but I believe it should be 500mA to suply the pic burner);

3-Make sure you are plugging the DC power suply into the right place, I've managed to explode my 7805 by connecting my power source to the probe plugs by accident;

Now turn ON the pic Burner....

3-Check the voltage your getting after the LM317 power suply circuit stage(you should manage to use the trimpot to adjust its output to 12-13V);

4-Do the same for the 7805(it should be outputing 5V);

5-Now check if you are getting voltage into your ICs:

  on IC3 :

    -put the black probe of your multimeter on PIN 7 (GROUND)  and the red probe on PIN 14 (VSS) and check if your multimeter is reading about 5V;

  on IC4 :

    -put the black probe of your multimeter on PIN 7 (GROUND)  and the red probe on PIN 14 (VSS) and check if your multimeter is reading about 5V;

6-In order to debug your PC connections:

6.1-open your burner (p18 or PBrenner) software and select 'HARDWARE' TAB after selecting 'OPTIONS' TAB.Now you have those little buttons that turn the circuit leds on and off;

    on IC3:

    -put the black probe of your multimeter on PIN 7 (GROUND)  and the red probe on PIN 1 (VPP enable);

    -Now press the 'VPP ON' button on the burner software and check if your multimeter indicates that voltage does'nt exist(it should be around 0V);

    -Now press the 'VPP OFF' button on the burner software and check if your multimeter indicates that voltage does exist(it should be around 5V);

    -put the black probe of your multimeter on PIN 7 (GROUND)  and the red probe on PIN 13 (VDD enable);

    -Now press the 'VDD ON' button on the burner software and check if your multimeter indicates that voltage doesn't exist(it should be 0V);

    -press the 'VDD OFF' button on the burner software and check if your multimeter indicates that voltage does exists(it should be around5V);

  on IC4:

    -put the black probe of your multimeter on PIN 7 (GROUND)  and the red probe on PIN 1 (CLOCK);

    -Now press the 'SCLK ON' button on the burner software and check if your multimeter indicates that voltage exists(it should be around 5V);

    -Now press the 'SCLK OFF' button on the burner software and check if your multimeter indicates that voltage doesn't exists(it should be 0V);

    -put the black probe of your multimeter on PIN 7 (GROUND)  and the red probe on PIN 6 (DATA OUT);

    -Now press the 'SDATA ON' button on the burner software and check if your multimeter indicates that voltage exists(it should be around 5V);

    -press the 'SDATA OFF' button on the burner software and check if your multimeter indicates that voltage doesn't exists(it should be 0V);

    -put the black probe of your multimeter on PIN 7 (GROUND)  and the red probe on PIN 13 (DATA IN);

    -Now press the 'SDATA ON' button on the burner software and check if your multimeter indicates that voltage exists(it should be around 5V);

    -press the 'SDATA OFF' button on the burner software and check if your multimeter indicates that voltage doesn't exists(it should be 0V);

7 - If all of this tests are passing so far that means that you have a good LPT cable and that your computer is comunicating with your programmer hardware, so now you should check your ICs output voltages in order to ensure that this chips are working properly:

    on IC3:

    -put the black probe of your multimeter on PIN 7 (GROUND)  and the red probe first on PIN 11 then on PIN 12 (VDD);

    -Now press the 'VDD ON' button on the burner software and check if your multimeter indicates that voltage is about 5V on both PINS(11 and 12);

    -Now press the 'VDD OFF' button on the burner software and check if your multimeter indicates that voltage doesnt exist(it should be around 0V);

    -put the black probe of your multimeter on PIN 7 (GROUND)  and the red probe on PIN 10 (VDD led);

    -Now press the 'VDD ON' button on the burner software and check if your multimeter indicates that voltage doesn't exist(it should be 0V);

    -press the 'VDD OFF' button on the burner software and check if your multimeter indicates that voltage does exists(it should be around5V);

    -put the black probe of your multimeter on PIN 7 (GROUND)  and the red probe first on PIN 4 then on PIN 5 (VPP);

    -Now press the 'VPP ON' button on the burner software and check if your multimeter indicates that voltage is about 0V on both PINS(4 and 5);

    -Now press the 'VPP OFF' button on the burner software and check if your multimeter indicates that voltage is about 5V on both PINS;

    -put the black probe of your multimeter on PIN 7 (GROUND)  and the red probe on PIN 6 (VPP led);

    -press the 'VPP ON' button on the burner software and check if your multimeter indicates that voltage is about 5V;

    -press the 'VPP OFF' button on the burner software and check if your multimeter indicates that voltage does'nt exist(it should be around 0V);

    on IC4:

    -put the black probe of your multimeter on PIN 7 (GROUND)  and the red probe first on PIN 9 then on PIN 10 (DATA IO);

    -press the 'SDATA ON' button on the burner software and check if your multimeter indicates that voltage exists on both pins(it should be around 5V);

    -press the 'SDATA OFF' button on the burner software and check if your multimeter indicates that voltage doesn't exists on both pins(it should be 0V);

    -put the black probe of your multimeter on PIN 7 (GROUND)  and the red probe on PIN 4 (CLOCK);

    -Now press the 'SCLK ON' button on the burner software and check if your multimeter indicates that voltage does'nt exist(it should be around 0V);

    -Now press the 'SCLK OFF' button on the burner software and check if your multimeter indicates that voltage is about 5V;

8 - Ok, if you've passed all the tests and still don't manage to work with your programmer then it can only means that you've missplaced or forgot some component. So you should re-check that all components are there and that they're correctly connected. Ensure that polarity of transistors and diodes is correct. Also You should be 100% positive that all components are healthy.

This turned out to be a bigger reply than  I was expecting, I've been recently debugging my programmer.It was giving me problems because of a faulty transistor, without this tests I would never had figured it out, so I hope this can help others with solving theire programmers problems....

Cheers

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So i checked the schematic and the PCB board, i forgot two ground pins, the R12 and the 7pin of the 74HC14. After soldering, i tested again and:

1) Power's Green LED stays OFF (BAD)

2) 7805 voltage regulator goes really really hot! (BAD)

How could it possible that the 7805 goes so hot after putting the ground at those pins?

Again sorry for my bad english, ask if you need more info. Thanks to all, you out there are very kind!

Gord The Rogue

Sorry. Be more accurate in schem reading ! Resistor R12 is connected to a +5volts rail, not GND !

MaY be this and the some similar connections causes a short circuit .

Regards, Janis

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Thanks a lot guys!

Yes the problem was that stupid ground connection to R12!

You were right Janis1279, thank you.

Now everything works, i've uploaded the MIOS and i've done/listened to the TestTone application.

But my LCD doesn't work, don't know why because i've checked the connections and all is fine. It turns on, with the B/L on but no strings appear on it, neither the copyright and "ready" strings. Weird.

Atm i'm doing a search into the forum, my LCD is this one:http://www.unitech-lcd-modules.com/pdf/Uc-202a.pdf KS0066 compatible.

Gord The Rogue

--------------------------------------------

Update: It was a contrast fault,i tuned the trimpot and now i can see something on the LCD, with something i mean black bricks on half screen (right side), no strings (no copyright logo). The visual is like this:

          blank      --------------------------- 5x2 pix  (columns X rows) brick

          blank      --------------------------- 5x2 pix

          blank      --------------------------- 5x2 pix

          blank      [][][][][][][][][][][][] 5x7 pix full black bricks

                              twelve columns

Need some more testing, maybe i must check the .hex configuration; my LCD is 20x2.

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