95 LT1 PCM (16188051) uses a 16202476 MCU !!

[Ken Kelly]

Tom,
	I'm confused. I thought the 96 LT1 PCM went to a 1024K Flash on the T side and
used the same 512K Flash on the E side. I have included recognition of the 96
chips in my editor. I don't have a set of the 97 prom images, so I haven't tried
them. I thought the 97 and 96 were the same. If you have data location for these
chips I'll build them into the editor. The checksum locations for the 95 seem to
work fine for the 96 E side. 

	Did you socket your PCM or dump the data through the ALDL port? I need to get
you together with Dave Hempstead. Hes doing the same disassemble for the 95.

		Ken

Tom Hussey wrote:
> 
> Hi,
> 
> I am sure the 16202476 processor is a MC68HC11F1. All the I/O port
> addresses line up with the data sheet. I can see from my disassembly of
> the '97 Camaro that the SPI port is manipulated on both processors for
> redundancy and how the data comm scheme works. Other chips I have
> identified are MC68HC58 for OBDII data comm, mc33291 or mc33298 for
> octal drivers. I have decoded the section that drives these chips.
> Anyone with part numbers? Flash used is 512K on event side and 64K on
> the timing side.
> The OBD chip is at $1060 and $1061 if anyone is interested.
> 
> -Tom
> 
> Ken Kelly wrote:
> >
> > Ludis,
> >
> >         Do you know which Variant of the HC11 this is?
> >
> >         The original posting was to try to identify which variety
> > of 68HC11 is in the 16202476? We are disassembling the 8051
> > EEprom, and the memory maps are different in the different
> > variants. We thought it was a 68HC11K4, but David Cooley,
> > thought that it was a 68HC11F1. Davids comments were based
> > on a P6 and I need to look at my board tonight, but I seem
> > to remember seeing P5 in the silkscreening.
> >
> >                 Ken
> >
> > Ludis Langens wrote:
> > >
> > > "David A. Cooley" wrote:
> > > >
> > > > I have 2 unidentifiable chips, 52 pin PLCC's, one is 56597 and
> > labeled
> > > > Delco, the other is labeled NCR and is 129170
> > >
> > > The ECM for the '95 2.2 L4 "4", 16191947, also uses a 16202476 and a
> > > 56597.  The 16191947  uses a MEMCAL with a 27_512.  I assume the
> > 56597
> > > is a two injector version of the buffer / I/O port / peak+hold
> > > controller which all the P4's use.
> > >
> > > Check the circuitry around the 56597.  Are there two diodes, two
> > 1.8K
> > > resistors, and two polarized capacitors, all hooked together and to
> > two
> > > pins of the 56597?  The old single injector controller uses these
> > parts
> > > to implement a voltage doubler.
> > >
> > > Other chips in the 16191947 are:
> > >      34987  O2 amp
> > >      34992  Power supply
> > >      34993  IAC driver
> > >   16045152  CD4011 quad NAND (?)
> > >      45153  CD4051 mux (?)
> > >      64606  ALDL interface
> > >      04891  ???
> > >      89551  ???
> > >   16132083  ???
> > >   16206550  ???
> > >
> > > --
> > > Ludis Langens                               ludis (at) cruzers (dot)
> > com
> > > Mac, Fiero, & engine controller goodies:
> > http://www.cruzers.com/~ludis/