[Diy_efi] info on 6800 motorolla

Alexis PAVLOV alexis.pavlov at st.com
Fri Jul 9 09:58:06 GMT 2004


Hi Remy,

I'm sorry to reply so, but I'm afraid you completely missunderstand
how an engine control unit (ECU) works. I don't think you'll
be able to find the solution by yourself as your request shows
you don't know much about microcontrollers.
Don't overclock the chip. It's not an Intel 666 processor, you
may damage it.
The 6800 knows nothing about engines, it's a generic microprocessor,
which needs additional external parts to get engine related infos.
The injection cut-off isn't just a switch, it's a software code
which compares the current RPM with some defined value from EPROM.
I'll need disassembling the EPROM code to find where the comparison
is done.

If you modify the input RPM related signal, the ECU won't be able
anymore to correctly manage the injection.

Alexei


> Remy Sabale wrote:
> 
> Hi ,
>      My engine is a toyota 4age  (tvis). i have check the ECU and it
> uses the 6800 series motorolla microprocessers.  My objective is to
> make the rev limitter or fuel cut off  a  litle bit much higher   ,
> because i'm using this car for autocross. i know someone that have
> done this but he would not share his secret.   the details only he
> give to me is that i must  intercept the signal going to the
> processors so that it will think that the engine is not reving high.
> 
> some one suggested to overclock it.
> i try to replace the crystal clock to over clock the processor, but
> i'm not satisfied with it. i find the engine not to responsive.
> 
> is there any other way to remove this cut-off?
> 
> what is the input pin of the 6800 for the distributor  signal( crank
> angle sensor)?
> any suggestion?
> 
> what component should i replace to remove the cut-off?
> 
> thanks,
> Remy
> 
>     ---------------------------------------------------------------
> _______________________________________________
> diy_efi mailing list
> diy_efi at diy-efi.org
> http://lists.diy-efi.org/mailman/listinfo/diy_efi
_______________________________________________
diy_efi mailing list
diy_efi at diy-efi.org
http://lists.diy-efi.org/mailman/listinfo/diy_efi



More information about the Diy_efi mailing list