Re: Clarification on Memcal issues

[Ludis Langens <ludis@cruzers.com>]

steve ravet wrote:
> 
> As I understand it, hardware cylinder select (a voltage level set by
> resistors on the memcal) only affects limp home operation.  The value in
> the EPROM is always used during normal operation.

The cylinder select in the MEMCAL controls the hardware _all_ the time. 
The cylinder select in the PROM is just for use by the software (and as
an idiotproofing check.)  Specifically, the MEMCAL determines when the
hardware timer chip is told to fire the injector(s) - every reference
pulse for TBI mode, or every 2, 3, or 4 pulses for port mode.  The value
in the PROM is used by the software to convert the reference pulse rate
to engine RPM.

-- 
Ludis Langens                               ludis (at) cruzers (dot) com
Mac, Fiero, & engine controller goodies:  http://www.cruzers.com/~ludis/
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