…I hear you scream.

Well Dear Reader, it has been very slow, but very steady.

I spent about 4 hours in the morning planning out the new display board.

After long and careful deliberation, I’ve decided that this board will have a two digit speed display -which you’ll be able to see your speed in either kilometers per hour (…for our younger riders…), or for our more ‘Senior’ members, the proper speed in good old miles per hour.  This will be accomplished at any time by just touching a button and it will flip over.

This display will sit towards the top right of the new board, and beneath it there will be a six digit timer (…HH:MM:SS  For the real bike enthusiast…) and you’ll be able to select from either incremental total time you’ve been cycling, or at the touch -and re-touch- of another button, you’ll be able to set time as a ‘countdown’.  By repeatedly pressing this, you will be able to increment your time-to-count-down in minutes that I haven’t decided on yet.  I think this will be experimental to see what riders think the time increments should be, but as its all in software, it’ll be dead easy to change after a few field trials.

All the displays will be in fetching green LED’s that are about 0.56″ high.  Easily viewable from the bike if the box is placed fairly near the rider.

Now, I could just about have handled this from just the one big 40-legged PIC (…the PIC16F887…) that I’m using for everything else, but I’ve chosen to have another PIC on this board handling these displays and buttons.


Well, if I had tried to run everything off the single PIC, I would have needed some pretty awesome software skills to get it all to work without falling over and glitching.  The displays would have been pretty ‘jumpy’.

This new PIC is the little 28-legged PIC16F876A.  This is from the same ‘stable’ as it’s bigger brother, so porting code -especially ‘C’ between the two- is no bother whatsoever.  They both have the same internal specifications, give or take the odd peripheral or two.

They also have virtually identical communications systems, so I plan to have the two of them ‘chatting’ using the industry-standard I2C specification I’m familiar with from my days with Bang & Olufsen (…They used to use this to communicate between processors and peripherals on their high-end music and TV/Video systems.  This was back in the late eighties, so goodness only knows what they use nowadays.  Probably fibre-optic…)

This also means that the whole system isn’t completely reliant on one single processor, and I have a gut feeling that this is the right way to go.  Don’t ask me why just yet, but I think it’ll pan out.

Now, whilst I know the I2C standards (…or can very quickly re-learn them…), I’m not quite familiar with how Microchip have implemented them, so that’ll be fun to learn.

By increasing my knowledge in this way, it’ll make it much easier to add further ‘whistles-and-bells’ further down the line as volunteers and users actually get to try this thing out.

And finally, as everyone who knows me knows, I’m a huge fan of flashing lights and ‘tell-tales’, so call it self-indulgence.  “Little Boys never grow up.  They just turn into Big Kids.”

“So where’s all the pictures you keep promising us, Wardo?”  Someone screams from the back.

They’re in my camera and safely backed up on my big back-up drive, ready to be processed at some very near date.

Don’t worry!  I have taken shots all the way through making this board, and I’ll be able to bore you to tears explaining just how difficult it is to use the hook-up wire I’ve chosen.  Thanks to the new camera’s awesome close-up facilities, I can get you right down to the heart of where I’ve been working.

Anyway, I’ve said too much already for fear of ‘jinxing’ it all, and as I’ve been sat at this bench more-or-less solidly since before 8.00 this morning, I’m starting to get a little fraggy now, so you’ll have to excuse me.

Oh, and only having had about four hours sleep in total since Saturday morning is starting to lose it’s ‘comedy value’ about now.

“Stop whining, you fool!”  Someone else jeers.  “You love it!”

Ah.  You found me out.

G’ Night, Dear Reader!


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