Din prob: button 13 doesn´t work

[Guest SK12]

hi,

button 13(according to mb64 wiring) doesn´t work.

I´ve already changed the chips, tested the pcb for shorts.

Any suggestions?

Thanks in advance, Sascha

P.S.: If everything is going well, my box will be ready on sunday, it´s design is roughly based on E-mu´s SP-12

[Sephult]

Have you tested the button? Maybe it isn't working.

:)

-Sephult

[Guest SK12]

Yes, also shortened pins on the chips to ground with a cable. But nothing happened.

[pay_c]

Reburn the software (verifying ok?), and perhaps even change the PIC once.

*Maybe* this could help.

Also check the wiring to the (and on the) core.

[Guest SK12]

I have 2 core´s, they are acting the same.

I think the problem is on the din.

[pay_c]

Yes, then it´s absolutely the DIN.

Recheck the wiring. (I  know this is stupid, but whatever, you know...)

Perhaps its not a short, but a broken PCB lane. Check the PCB lane of that button.

And try to pull the pin of the IC directly to ground. I mean directly at the *pin*, not the jumper conn.

You dont eventually have a second DIN ?  ;D

[Guest SK12]

I shortened the chip pins to ground, all fine except button 13.

As i´m helping a friend to build one, i´ll will soon have a second Din to check.

[pay_c]

Really??

Hmm, I´m getting out of ideas with the time..... but as its only that one pin, thats not working, it should be something with its connection.

Do me a favour, and measure the voltage of that pin, it has to be at 5V without a pressed button. With pressed button it should go down to 0V. Perhaps then we know whats up.

Really weird up to now... :P

[Guest SK12]

The pin is already at 0V(without button pressed)!??

[pay_c]

Then its definitely a short one or similar. Check the resistor of that pin, perhaps its broken and doesnt pull the pin up to 5V.

Somehow the pin has to be pulled to 0V. So its either a short one to ground or a broken resistor!

Now at least its clear now: Its not the ICs, not the core, and so its definitely something at pin 13: a short or the resistor.

Hope that helps at last!  :)

[Guest SK12]

Yeah, problem solved!!!

Thank you, it was a shorty.

[pay_c]

At last, got it!  ;D Cool. 8) Have fun then!