programming 101 and checksum

[Shannen Durphey]

Vance Rose wrote:
> 
> At 07:01 AM 8/9/98 -0400, you wrote:
> >
> >-----Original Message-----
> >From: Shannen Durphey <Shannen at mcn.net>
> >To: diy_efi at efi332.eng.ohio-state.edu <diy_efi at efi332.eng.ohio-state.edu>
> >Date: Sunday, August 09, 1998 3:13 AM
> >Subject: programming 101 and checksum
> >
> >
> >>Memory location 0x004 is listed as the checksum enable for
> >>7747 ecm. This value is $42 in my factory files.  Does
> >>anyone know what the value is to disable checksum?
> >
> >AA
> >
> > Also,
> >>this location in 8747 ecm contains the value $4F.  Is it
> >>safe to assume this is checksum enable for this ecm?
> >
> >I don't know, could try a chip with AA entry and see
> >
> >Bruce
> >
> >>Thanks
> >>
> >>Shannen
> >>
> >
> >Hi All
> 
>         If ya have time - just disassemble code. The checksum is usually early in
> program section. Being a novice it was one of my first finds for 165 ecm.
> 
> Vance

Ummm, you make it sound so easy, I wish I knew what you
meant.  I've looked at disassembled code on Ludis' site, and
it's pretty much Greek to me.  So where's a guy to go to
learn more?

Shannen