I've been working to get my new game score keeping device up and running in time for the Brighton and Hove Petanque tournament this Sunday. I'd coded it up pretty quickly, but when it came to saving the results to EEPROM, I quickly discovered not just the limit of the available memory, but the program limit of the 16F628A. I'd filled up my allocated 2k of program memory and still had about 40-50 lines of code left to go!

A bit of jiggery-pokery and some sub-routine optimisations and I managed to squeeze the entire code down to just 1600 words (but sacrificed some nice bits in order to get it working).

I was keen to see it working in hardware and dumped it all to a chip.
I plugged it into the breadboard and fired it up.
Nothing.
Zilch.
Zero.
Nada.

Then something.
A small wisp of smoke.
Then a lot of smoke. Holy crap! I'd plugged the micro in upside down, forcing 5v onto its ground pins and driving the 5v low. It's been a long while since I've done that. But it goes to show that even when you think you know what you're doing, there's no room for complacency! I could have fried my USB port just now.
Thankfully the only thing I lost was a cheap 99p microchip!

Since I thought that making a PIC-based project would be a bit of a laugh and probably while away a few hours. However, it's been one nightmare after another (with long periods of waiting in-between). First off, getting hold of a PIC programmer proved a disaster. When I finally got one, I bought in a load of 16F628A chips (ok, four) and a usb-to-serial chip on a breakout board. Deciding that this would be too expensive to use for the hundreds of ideas I had bursting around inside my head, and that it wouldn't be too difficult a job to use the much cheaper (and smaller!) surface mount chips, I set about a circuit layout that allowed me to use these two reasonably-priced components together.
Then I found out I was rubbish as surface mount soldering.
But that might also have something to do with being unable to get a decent toner-transfer image, despite trying four different photo papers and even some hand-drawn traces with indelible marker pen.

I've heard good reports (and bad, funnily enough) about Press-n-Peel paper.
Given that I've not managed a single 100% successful image using the toner-transfer method, I thought I'd better give it a go.

But while I was waiting (again) I thought I'd investigate the how to actually implement real USB, using the 18F series of chips. And it looks quite feasible. So now, I've used my first sheet of Press-n-Peel (at a cost of about £2) and finally managed to make a PCB with no broken traces or fudged hand-drawn lines. It worked a treat! But I'm still rubbish at surface mount soldering and decided to bin the whole FT232RL chip idea.

So I now have a perfectly formed PCB, but the pin layout only works with components that I've since decided not to use.
Bugger.

Only a few more days before my 18F2455 chips arrive in the post and I can pretend that the last two weeks never happened, and maybe even get at least one circuit built before I go away on holiday (in August).