foft's dfb1 build

[frank.lukas]

That's not difficult. You need the right tools and a steady hand. There are still 4 boards left. Practice creates masters ...

[Badwolf]

Bad luck with that one. It may still be salvageable, but if you have spare boards it's probably easier to start again.

I must have soldered a couple of dozen of those CPLDs by now, some I've had on and off three times as I wasn't happy with it. The worst is when you bend a pin (looks like you have one there, actually) and the whole lot has to come off even if everything else is perfect.

Sometimes I've buggered up the CPLD so much it's in the bin. That hurts at normal prices. Now it's a proper gut punch!

However once you've done it correctly once (and re-done one once to boot), you'll wonder what all the fuss was about. Flux. More flux. And if you're not sure, try more flux. I do use the iron, though.

All that said, however, the CPLD is still the first thing I'll solder on a board when I'm building one up, as it *is* the hardest thing to get right and if you really muff it up, you don't have to do all those damned passives again!

Good luck!

BW

[foft]

Second attempt going better.

I soldered it with lead free this time and using a concave chisel tip. After sticking it down with kapton (after much adjusting!) I tacked the two corners. Then I put some solder onto the tip and approached from the edge. Soldering 2-3 pins at once that way. edit: pics later...

After transferring all the decoupling caps I put on many other tiny parts to get up to the program part. Recognized and programmed.

So, on to the next part tonight - or another day. I'd better go and speak to my family before they disown me!!

[foft]

I put on the CPU and headers etc, then plugged it in.

When disabled, the falcon still works.

When enabled and no 'flash_dis' jumper I get a screen, but corrupt. I guess I have no flash so that would be expected.

When enabled and with 'flash_dis' jumper I get a no sync.

[foft]

Tried another 68030 just in case, same thing.

Checked the CPU clock (50MHz) and FPU clock (25MHz).

So back to checking my soldering...

[DoG]

Try removing FPU. Disable onboard flash. There is a jumper for 64Mb/128Mb as well.

[foft]

I was working through the build as described on the bom, I’m up to the ‘falcon should now accelerate’ part. I’m not up to the ram, flash or fpu yet. I do have an fpu on the falcon but guess that is harmless here.

I guess I should give it a really good inspection and if that doesn’t turn anything up I could try a custom Jed to toggle pins and check that.

[foft]

Some pics so far:

CPLD_BETTER.JPG (268.37 KiB) Viewed 1853 times

CPLD_BETTER2.JPG (228.15 KiB) Viewed 1853 times

CPLD_BETTER_TOP.JPG (242.5 KiB) Viewed 1853 times

CPLD_BETTER_BOTTOM.JPG (306.62 KiB) Viewed 1853 times

[foft]

Last minute late night check - found a couple of pins that were not well soldered on the CPLD.

Plugged it in and...

gembench.JPG (308.37 KiB) Viewed 1843 times

[foft]

BTW does the flash chip now work on the latest jed? I didn't order that since I thought it wasn't ready yet.