New Microchip PIC processor.

[rr]

David A. Cooley wrote:
> 
> At 05:16 PM 6/8/99 -0700, you wrote:
> 
> >
> >really?  that's interesting.  i guess i didn't think that they could hack it
> >b/c
> >they run at about 2MHz, don't have a lot of I/0 lines (unless you get the 52
> >pin),
> >and were generally pretty old.  i guess that's my fault.  i figured that
> >there were
> >better out there.
> >so, let me rephrase that, HC11's could hack it, but they can be improved upon.
> 
> GM's use in 93 and up is the HC11F1... Lots of A/D, IO, address space
> etc... they run the external clock and 12.something MHZ... internal is 4MHz
> at that external rate...  Up until OBD_II, data I/O from the HC11 based
> PCM's was 8192 baud... OBD_II is 10.4KBPS VPW.
> Most of the later PCM's have 2 CPU's (Both HC11F1's).. I believe one is
> dedicated to nothing but spark control.

This doesn't surprise me (a cpu dedicated to ign ctrl). From what I've
seen, spark takes a lot of table space and code space. It's easily half
of the available system. GM finally went and just split the task per cpu
in half.

BobR.

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>            David Cooley N5XMT           Internet: N5XMT at bellsouth.net
>      Packet: N5XMT at KQ4LO.#INT.NC.USA.NA   T.A.P.R. Member #7068
>    Sponges grow in the ocean... Wonder how deep it would be if they didn't?!
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