ALDL Updates was DIY-WB Output Voltage Scaling

[rr]

Actually the ECM doesn't have to worry about this kind of stuff. Everything
is internally timed to run at certain rates no matter the RPM.  There are two
minor loops that each run 80 times/sec (fuel & spark). Then there are 16
major loops that run at 10 times/sec. Then there is the kernal scheduler that
runs at 160 times/sec.

The RPM related stuff that controls spark & fuel all runs in hardware. I haven't

looked at the 8192 buad aldl too closely. However the 160 baud (bps) sends
a bit at each kernal loop, 160 times/sec.

BobR.

Vim Fuego wrote:

> > The only thing that's fixed is the baud rate (8192 baud) which means you
> > will never achieve more than 800 or so bytes per second. The mode 1
> request
> > string is 5 bytes long, so 10 requests a second accounts for 50 bytes, or
> > 6% of the bus bandwidth.
>
> O.K, but the 'main' job of the ECM is to run the engine right!, so any
> serial data routines must be lower on the priority scale?, so if the motor
> is running at say 3,000RPM, how long does the ECM have to service the serial
> data routine without having to ignore it and get back to it's primary
> function?. Surely that (as well as number of bytes transmitted) dictates the
> update rates?.
>
> Vim
>
> ----------------------------------------------------------------------------

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