CPU's

[Ludis Langens]

Bob Wooten wrote:
> 
> So let me see if i have this straight.  the BCC is not in the firmware,
> though the prom ID is.  the prom ID has the detailed information specific
> to the application & it can lead one to the BCC.

The scan id in the chip does not have detailed info.  If you are lucky,
the scan id by itself is enough to figure out the matching BCC.  Usually
you have to use the context (what mask byte, what year, what engine,
etc.) to get from the scan id to BCC.  If you are unlucky, one
ECM+mask+application will have duplicated scan ids.  Someone posted such
a chip on incoming.  Its one of two possible BCCs, I don't know which.

> here is what i am not following, you said that the Mask byte (not two bits,
> forgot the Basic EE from school), "might not have the same table layout".
> so, this means that there really is not a simple rule here.  i was thinking
> (assuming i suppose), that this being the truth would make it rather easy
> to write stuff like Win Bin & Tuner Cat for that Mask byte.  it appears
> not.

There at least two-each of masks 32, 6E, and 8D.  The changes might be
bug fixes with unchanged table layouts, or an extra table or constant
might have been added.  The paranoid chip editor should be checking
either the program code or perhaps some of the table headers.

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


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