Re: reading flash chips... was: Re: Looking for a 16149396 ECM

[Scot Sealander <Sealand@clarityconnect.com>]

ECMnut@aol.com wrote:

> I really want to play with flash stuff too..
> Assuming you could read that in the same manner
> as a regular prom (is that a big assumption?)   What sort of
> voltages do you use?

Mike, the flash could be read in a regular PROM reader. 
One challenge is that the flash chip is a PLCC, soldered 
on the board.  I suppose one could remove the chip, get or
make an adapter to fit the PROM reader and read it.

I tried to read one of these ECMs with a piece of code
that reads P4 PROMs over the ALDL, and it did not spit out 
the program.  Near as I can figure out, to read these things
over the ALDL, you send it the needed code, which gets loaded
into RAM.  The RAM code takes over and reads the flash code 
and sends it out the ALDL.  This is why it is so important 
that you never lose power after the flash is erased.  There 
is no easy way to put the load code back into RAM!

So it may take a bit to get this going.  But it is an SFI
6 cyl ECM, and it may be MAP based  Looking foward to getting 
it to work!

Scot Sealander
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