Selectable chips & boost programming

[David Cooley]

At 10:38 AM 2/25/2000 , you wrote:
>David,
>
>Do you have the specifics on how this is done ? I'm VERY
>interested in doing this...I'd like to run a nitrous program and
>"regular" program--and a program for high octane on TBI
>stuff...

Don't have anything in hardcopy, but it used a 27C128 chip stock, so I used 
a 27C010, mapped all the similar address, Data, power and control lines to 
a 28 pin plug so the plug looked like a 27128 to the ECM. Took the 3 
additional address lines and ran them to a BCD thumbwheel switch, and the 
Thumbwheel switch I believe grounded the lines when they were active (I 
could have that backwards...) and used pull-up resistors on the lines to 
the switch. I loaded a program into the burner, set the switch on the 
number I wanted that program to be in the chip, and burned it, loaded the 
next bin, set the switch to where it was supposed to be and burned it, etc. 
You could switch programs on the fly without a hiccup out of the engine 
(unless you were screaming and selected valet or security mode!). Worked great!


===========================================================
David Cooley N5XMT Internet: N5XMT at bellsouth.net
Packet: N5XMT at KQ4LO.#INT.NC.USA.NA T.A.P.R. Member #7068
We are Borg... Prepare to be assimilated!
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