Oversized EPROM's & Multiple Programs

[944Technologist]

> You will have to verify that the socket pin 1 is
> connected to "A15".

Correction: You will want to isolate pin 1 from buss "A15" so as not to
interfere with the normal operation of the ECU.

FR Wilk
___________________________

From: "944Technologist"
> DME stands for Digital Motor Electronics and is the same thing as ECU.
>
> To go from 27256 to a 27512, pin 1 goes from "Vpp" which is used only in
> programming to "A15". You will have to verify that the socket pin 1 is
> connected to "A15". Your goal is to add an external switch that changes
pin
> 1 from 0V to 5V. This gives you 2 banks of 256K to run different programs.
> If you need to change on the fly, rig the same switch to interrupt power
to
> the ECU until after the bank switching has taken place.
>
> I have to kill the ignition to switch programs. I was on an uphill grade
> with the wrong gas and started to knock. So I turned off the ignition,
> flipped from performance to stock program, and then restarted. 5 seconds
> total. The only time I wanted to switch while on the move.
>
> Best of luck,
>
> FR Wilk
> 84 944 Porsche
> ______________________________________
>
> From: "Walter Sherwin" <wsherwin at home.com>
> > Thanks.  What's a DME?  When you say power down, do you mean key-off
> > engine-off, then switch, then key-on and run, or simply reduce power and
> > switch on the fly?  Appreciate the feedback.  My bud says thanks.......
> >
> >
> >
> > >I have a DME operating with an external switch for 2 different programs
> on
> > a single EPROM. One performance program and a second is the >stock
> program.
> > You have to power down to switch programs.
> >
> > >FR Wilk
> > >84 944 Porsche
> >
> >
>
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