Using PC HW

[Woodd, Michael]

Flame on full:
I've just *begun* using a Philips 8xC552 uController, and the thought
of the time and effort and extra hardware in using a PC to control
a car makes me want to PUKE!!!!!  Not to mention how FECKIN' BIG'N
UGLY it would be!!!!!  Forget it!!! All this wasted bandwidth is makin
me vomit!!!

Flame off, nice cool air conditioning on.
If you want to DIY a engine computer heres a list of 552 features:

8  10-bit A/D inputs or switch inputs (any combination)
     obvious uses ;-)
2 variable frequency/duty PWM outputs
     motor control/ DA output with integrating op-amp
2 8-bit or 1 16-bit timer
1 more 16 bit timer (Timer 2)
1 serial UART
1 I2C bus (100kHz serial bus) port
2 timer controlled toggle outputs (T2)
6 timer controlled set/reset outputs (T2)
     use for DDIS ignition (or not) and Injectors
     These have registers to compare to T2, set them and
     the outputs happen automatically at the correct time
2 external interrupt inputs
     input(s) from crank sensor(s)
     for V engines, easier to use two sensors
Spare digital outputs for pretty much anything simple

Timer resolution is 1/12 of processor clock speed.  At 12MHz
typical clock, we get 1uS timer resolution.  A 16Mhz version
exists too for that little extra grunt.  All this on one PLCC64 chip!
Too easy to make a single layer board for.

Buy/get the Philips 80C51 family databook.  The 1991 version I
have has an application note describing managing an engine in
sufficient detail to make it look like a doddle (of course it wouldn't
be but it's a better start than you'll get anywhere else I'll wager).
If anyone wants I can give the Philips AN number.

Development hardware is not hard to find, although I dont know
for sure cos I use a homebake system I borrowed from my
former employer, including 32k EPROM, 64kRAM, romless
80C552, memory interface buffer etc.

Well anyway, I'm now in a good position to seriously look at
doing this thing, having just got over the initial hurdle of basic
assembly programming, burning EPROMs, setting up a
dot matrix LCD display, led outputs etc.  Now for the hard stuff...

Mike Woodd
(wooddm at akcity.govt.nz)

Nearly forgot: Air conditioning off.