Well I've built my own speedo with an LCD read out. It works quite well at the moment - I have a few mods in line for it, but the only bad thing about it at the moment is having to clean IR speed sensor ever few hundred ks or so.
The readout accuracy is +-1km/h, the odo readout increment is 600mm (yes only 0.6 meters!) and tacho readout. It also has a trip meter with the distance, engine running time and the number of revolutions the engine has done on the trip!
Some of guys have expressed interest in making one for them selves so I'm sticking the code and schematics that I used up here.
Heres the schematic: (Big gif)
http://middleparkmadness.homeip.net/...speedo_sch.gif
Righty, the assembler code is now available. Heres the zip file:
http://middleparkmadness.homeip.net/speedo_code.zip
I used MPLAB to assemble and for programming - you'll still need some hardware in which to connect between your PC and the chip though. You can download MPLAB for free from the Microchip website: http://microchip.com/stellent/idcplg...&part=SW007002 or if doesn't work just follow your nose from http://www.microchip.com/
The main file to assemble is speedo.asm - this includes all the other ones automatically.
The programming hardware I used was a ICD2 - you can get them from microchip for about $160US or find someone to borrow off.
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