bdu

In the end, swapping in a new, programmed pic did the trick. Now to wire up all that AIN...

I noticed no one has mentioned the 808's nifty A-A/B-B switch... damn that thing is handy.

Note that while the PIC is the only thing carried over from the previous board, that's not the same pic I gave 12v, that one was very obviously dead, this was the second pic on that board, one I didn't put in until after I thought I'd ironed other stuff out. Nothing else built but the LCD connected, and even that not all the time. I agree that it's the likely culprit, given that nothing heats up like that with it out, but then again, nothing is drawing current if the pic isn't in... I was just wondering if anyone had seen a dead pic heat up like that, to confirm my inclination, since it all tests fine with the pic *IN* too, just the heat issue, you know?

You mean pic, right? I never got far enough to even think about a sid! ;0) Yeah, I'll double check my voltages and maybe replace my 7805 before putting the new one in (just in case the extra heat did it any damage). Thanks.

I was trying to avoid asking for help, as I like to puzzle these things out for myself where possible, but I'm at a loss for ideas. Here's the scoop: A few months ago I built a core board (r3 from smashTV), did something really stupid after assembly (put 12v dc on j2 instead of j1, whoops), replaced the sensitive components (all ICs, anything that smelled bad), tried to power up (correctly this time), and all I got was very hot rectifier, 7805, and pic. No midi, nothing, and I'd have to power down inside of a couple of minutes due to the excess heating. OK, time to cut my losses and start over, as I'd made a real stupid move with that first board, and I didn't feel like shotgunning it. So a few weeks ago I bought another core board (this time r4 from smashTV, much cleaner, BTW), assembled it, and I get the same issue. Here's the details for anyone wanting to think about the issue a bit to help me out: 1) I've checked all the 5v pins and all the gnd pins, they're all good whether the pic is in place or not. 2) I was very careful to get all polarized components in with long leg positive. That is the standard, right? 3) All ICs are in with pin 1 in the correct place. 4) I'm supplying 9v AC 1A at j1, the 7805 is putting out a good solid 5v. I've also tried DC supplies at lower voltages... they all do the same thing. 5) If I pull the pic from the board, the 7805 doesn't heat up like this, this seems the best clue? 6) I went through and did a reflow on any and all joints that looked dodgy. 7) If I power up with my LCD in, I get a bunch of block chars on the bottom row. 8) I don't believe there's any midi comm going on, at the very least, no requests for bootload. 9) I definitely can't leave it up very long with the PIC in place, as it all heats up dangerously hot. Now, the PIC is one that I'd had before (the second one from the first core board), I've ordered a new one, but might a busted pic be the source of all my trouble here? Is this a known failure state for them or? I'm not a total n00b, I've successfully built other things (x0xb0x, midisense, midi2SDSII, etc) without any major trouble, and given that my voltage test points all seem good, I doubt it's my soldering. Any ideas, guys? Much thanks in advance for any help you can offer.