Need help troubleshooting core

Testing/Troubleshooting
1

I ordered a PIC preprogrammed with the MIOS bootloader from SmashTV’s site, dropped it into my core (with a SID attached) and hooked it up to my computer to put MIOS and the SID app into it with MidiOX, but when I power up the core, I get nothing coming into MidiOX, let alone the Sysex sequence that announces the unit is ready to recieve programming via Sysex. All that I do get is some seemingly random pitch bend messages when I disconnect the power to the core/sid, but I’m guessing this is probably just garbage data.

Both the core and the sid passed the voltage tests, so what should I be looking at here? WHere should I start?

Thanks!!

2

hi,

Had the same problems with one core…this had a shortcircuit…

Did you check your midi-connections? Connected in the right way like as descriped in the schematic of the core?

Check this first, then your soldering on the core from your midi-out lines (follow the routes)…all points soldered in the right way…?

Maybe this helps…maybe not…it’s a kind of guessing…

But sounds like shortcircuit…between ground and the lines out of Midi-Out…

Hope this helped…

Grtz …  Erik

3

Hi.

Yeah i think many people have had these problems, my self included.

Have a look at what steps i took to get my core working here -

http://homepage.ntlworld.com/keith.williamson/midifaq/midi%20faq.htm

Let us know if this helps!

PW

4

Hey, thanks for the pointers!

Hopefully I’ll have a chance to try out these ideas tomorrow.

5

yes 95% of the time it don’t work for a “stupid” mistake :slight_smile: we all make some, so double check everything!

Hey Pulse, why don’t you put yout tutorial on the  portal? I think I have things to add to it :wink:

6

OK, I’ve re-checked my voltages, all good.

Also went over my PCB traces both visually and with my meter when in doubt, no shorts, no cold joints. (OK, there were two cold joints, but those weren’t the problem).

Triple-checked wiring of MIDI-out, and ensured MIDIOx can recieve data through the cable by tring it with my midi floor controller, all OK.

I tried the LED test that Pulsewidth suggests, and tht failed.

Only thing I can think of that hasn’t been tested is the crystal. What’s the procedure for testing the crystal? I’ve got an old scope in the dining room…

7

sometimes the mistake is much simpler and way much more STUPID!!!

I once placed the PIC wrong! (pin 2 was where pin1 should be!) so 2 pins where on the air!

It took me hours to find out what I had done and felt really stupid!

(btw, the pic was not blown and it works fine now!)