chipping the ECU?

[Bostedquest]

I am not afraid of soldering, or electronics is general.

I was wondering if it was possible to chip (install a dip socket) in a non chip ECU?

 

[steve]

I was wondering if it was possible to chip (install a dip socket) in a non chip ECU?

Anything is possible but in this case it's not practical. First, we don't have the information on how to disable the mapping of the internal PROM into the address space and thats requires in order to hang an external EPROM on the bus. Second, the CPU uses a multiplexed set of pins that are shared with some of the IO ports for the address and data lines. The EPROM ECU has a custom chip that acts as a port extender remapping these IO ports to the external chip and so that those lines can be used for address and data. The only place to get one right now is off a EPROM ECU.

There was(still is?) a company that made a board for this but it cost $700. Not really a effective solution when you can buy a EPROM ECU for less than $300.

If you want to know more read up on the M68HC11 architecture. The CPU used in out ECU's shares much of it. The sections on basic and extended systems will help you understand what the issues are even if the specifics are different.

Steve