Some of you may be already aware that I've begun a project with the intention of interfacing to the Power FC for a low cost, open (as possible) hardware and software solution.

The beginnings of this are here:

https://www.rx7club.com/power-fc-forum-47/fc-tune-preview-439195/page39/

My aim is to collate as much of the existing information as possible into a coherent archive, so that anyone with basic electronics can DIY an interface, and get useful information using it.

Taking it stage by stage my intentions are:
1. Build or source a working, reliable, safe, interface for under 30 UKP
2. Encode the already published command structure into a linux/ OS/X - based (its what I know) API for talking to the ECU
3. Perform basic live monitoring of ECU parameters
4. Perform high level configuration of ECU
5. Perform fuel map analysis
6. Produce a decent GUI.
(in that order)

If anyone wishes to contribute in terms of knowledge and experience or other efforts, that would be most appreciated! - feel free to chip in and

What I am *NOT* doing is trying to produce a tuning system from the word go (though with a sound basis, this will come naturally later). My main motivation is the lack of live parameter monitoring that one suffers when you lack a hand commander ! This is an exploration of what is possible, not an attempt to produce a sellable product, nor trample on the toes of existing, proven systems.
My primary driver is cost. This is likely to slow things down a little, but once a basic interface is up, then I suspect things will take a different direction.

I do not intend to reverse engineer any of the very good software already available - I intend this project be done from first principles or public published information.
(Just so its clear :-)

All input gratefully received,
Feel free to comment on any part of this!
P.S I chose this board, as it it already a centre for this sort of information.
Thanks,
Edwin

 

Sounds like a really good project!

As I said on the other thread I'm looking to get my hands on a data sample from the Apexi ECU so I can have an interface cable produced that will connect up to my digital dash. Ideally through the s-video style pin out or through the datalogit serial connector.

The Race Technology shop offers CAN and OBI and OBII interface options so the dash unit can talk to the car. Unfortunatly the FD RX-7 isn't any of these! They have said if I can get a data sample they can make up an interface cable for Apexi users.

 

I thought our car was OBD-I.

 

Edwin,

As I said in my pm to you. I am willing to help in any way possible and once I collate all the info I have, I will pass it on to you.

 

Many thanks meddler :-) It's been slow progress due to holidays so far, but I intend to hitch up a laptop to the USB interface at lunchtime tomorrow to get some testing done.

bean-bandit - thanks for the enthusiasm! For the time being, I'm targeting only PowerFC->Laptop interface in order to get some groundwork done - this means USB interface only, and basic data capture/analysis.
Once its been taken quite a few stages further, then I see no reason why some code could not be written for specifically interfacing to digital dash, and embedding that into a microcrontroller - though I believe that this requires understanding another protocol, like OBD-II /CAN and the assorted hardware to do it. I think thats a much later project!

One of the problems with the Power-FC itself is that it appears to be pretty chatty, and there's a lot of data - thats why most analysis has been done at the upper level, after the bus protocol has been translated into real numbers/packets.

Hope to make progress soon,
Edwin

 

Any updates Edwin?