Transmission Configuration

[Ludis Langens]

Shannen Durphey wrote:
> 
> I found a neat one.  1990 m/y Vette w/ 6spd trans comes equipped with
> APYP calibration.  That's an auto trans calibration.  I thought it was
> a fluke until I found another the same way.

APYP is supposed to be a 1989 manual (ML9) calibration.

> Then again, if you go
> look up a 1990 Vette w/6spd calibration by application there's none
> found.  Maybe GM didn't have time to certify a manual trans
> calibration?

How about ARFP?  Interestingly, it's for both automatic (MD8) and manual (ML9).


The FWD cals usually have an options flag byte in the PROM, of which the
0x80 bit selects a manual transmission.  Look for a LDAA/BPL or LDAA/BMI
sequence followed by a table search.  This search is figuring out what
gear the manual transmission is in.  It'll probably use a CPX #nnn to
detect the end of the table.  There are very few CPX of an address
pointing into the PROM data area.  That makes it a good way to find this
function, and from there find the options byte.

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