rusefi.com

Hello all,

Thanks for re-igniting my DIY EFI aspirations! I've been interested in DIY EFI and rodding for more years than I care to admit. Back in college I cut my teeth on the wonderful Motorola 68HC11. I remember pouring over the EFI332 website way back in the day, thinking how awesome would that be. But, realistically the best entry-level option back then was to retro-fit a stock GM ECM. But any mods required another level of hacking. Until some of the guys like TunerCat came around.

I've been employed in hardware and firmware development for about 20 years now. I am currently working with Microchip uC's, but I've worked on other devices in the past. I code mostly in C and Assembly, but am familiar with other environments.

I've been out of the DIY EFI scene for a while, so I'm coming back up to speed with the latest happenings. In the past, I installed a MS2 system on a friends '84 FJ, and that was fun. But I've always been a little less-than-enthusiastic about MS in general. It works, but the design has some really non-standard strangeness that doesn't excite me. Entire code in ONE source file, really? Documentation was really scattered last I used it (but maybe that has improved).

However, rusEFI is looking pretty promising. It seems like a strong project with fundamentally awesome "mission statement", which I am quite supportive of.

I need to spend some more time perusing the Wiki, but I'm definitely ready to jump in right away. I've set a short-term goal to get my '65 Suburban 4x4 converted over to EFI. It has a 70's-era Cadillac 472ci V8. 2-injector TBI is what I have to start with. I had been considering MegaSquirt for lack of options, and there's a possibility I might acquire a free or cheap MS which I could temporarily employ. But ideally I'd like to get involved with rusEFI and use this instead, if it is practical. Development seems fairly active... am I right? I also have a truck and boat with the same engine platform (yes, I have a strange obsession with the monster Caddy motors), so whatever development I do on this first vehicle will be leveraged on other projects also.

It doesn't look like anyone has installed rusEFI on an 8-cylinder yet? And most of the installed engines are newer technology, PFI, distributed coil, etc. Is rusEFI a viable choice for me? Any advice on how to hit the ground running is very welcomed. A few prelim questions that I may find more answers to in the Wiki are....

- I'll be using GM TBI, which means 2-injectors, IAC, TPS, MAP, distributor-based trigger, single-coil ignition. The Wiki says "Devices not yet supported: IAC stepper, electronic throttle body" That sounds like it applies to me! Uh oh! What are my options?
- Considering my engine, which would be the best hardware to start with? STMDiscoveryF4, Frankenso, Frankenstein?
- Where can I help with the firmware?

Looking forward to getting involved!

-Matthew

Welcome along.

Stepper IAC hasn't been developed yet, I can point you to an off the shelf pololu module that could be installed into the proto area, then it's a fairly small effort of soldering and mostly software integration. Also electronic throttle body doesn't sound like you. That's drive by wire stuff found on newer engines. AKA replace the throttle cable with a wire and do it electronically.

You say 2 injectors, so that's lowZ? Frankenso handles highZ, but could be connected to lowZ via jbperf external box that converts a highZ to lowZ. How many ohms does your injector measure? If it's around 12 to 16 ohms, that's highZ, if it's significantly less ohms, that's lowZ. HighZ draws about 1A, and Frankenso can handle that kind of current. However lowZ draws around 4 amps and would not function well thermally.

To me it sounds like it's not very far off to have your V8 running with rusEFI.

I believe russian has a ticket system where he keeps track of features he's working on. If you are a software fellow, perhaps you can help with some of those tickets. I believe many can be developed with only the STMdiscoveryF4 board.

We are aiming for a spin of R0.4 in the near-ish future, but we are trying to iron out a no start issue with the knock sensor chip. We have followed a great many design guides, but for some reason this XTAL appears to not be starting correctly. As soon as we touch it with a scope probe it starts to oscillate. Any chance you happen to know about XTAL issues?

Hello and welcome!

Matthew wrote:- Considering my engine, which would be the best hardware to start with? STMDiscoveryF4, Frankenso, Frankenstein?
- Where can I help with the firmware?

STMDiscoveryF4 is a board which hosts the actual stm32f4 chip. both Frankenso and Frankenstein are i-o board, pretty much the same thing. You can solder the stm32 chip right to Frankenso but not anyone would be capable of this soft of fine-soldering.

https://sourceforge.net/p/rusefi/tickets/ lists all the open tickets, some are firmware/C, some are dev console/java. You would probably need at least STMDiscoveryF4 to work on most of them, we can REALLY use software development help

kb1gtt wrote:Stepper IAC hasn't been developed yet, I can point you to an off the shelf pololu module that could be installed into the proto area, then it's a fairly small effort of soldering and mostly software integration.

OK. Perhaps I can help with that. Would the idea be to eventually integrate that hardware into the controller? The Polulu modules came right up when I did a search for stepper motor drivers. I like the one based on TI DRV8824/DRV8825. The interface and requisite software looks quite simple. At least 2 or 4 outputs are required from the MCU. Although, it could be interfaced through a 1-wire chip to use only 1 MCU pin, or 2 if the fault feedback is desired.

kb1gtt wrote:You say 2 injectors, so that's lowZ? Frankenso handles highZ, but could be connected to lowZ via jbperf external box that converts a highZ to lowZ. How many ohms does your injector measure? If it's around 12 to 16 ohms, that's highZ, if it's significantly less ohms, that's lowZ. HighZ draws about 1A, and Frankenso can handle that kind of current. However lowZ draws around 4 amps and would not function well thermally.

Yes, low-Z. 1.6 ohms minimum. Thank you for the tip about the jbperf board. I assume you are referring to this one... http://jbperf.com/quad_ign_inj/index.html. Nice. Looks simple enough.

kb1gtt wrote:We are aiming for a spin of R0.4 in the near-ish future, but we are trying to iron out a no start issue with the knock sensor chip. We have followed a great many design guides, but for some reason this XTAL appears to not be starting correctly. As soon as we touch it with a scope probe it starts to oscillate. Any chance you happen to know about XTAL issues?

Touching the XTAL with the (analog, I assume) scope probe is effectively adding capacitance. So you might try increasing the capacitance. Also, maybe try adding a 1 or 2 megaohm resistor across the crystal. Maybe you've already tried these things though. As short as possible traces and connections at the crystal? What knock-sensor chip are you using?

russian wrote:STMDiscoveryF4 is a board which hosts the actual stm32f4 chip. both Frankenso and Frankenstein are i-o board, pretty much the same thing. You can solder the stm32 chip right to Frankenso but not anyone would be capable of this soft of fine-soldering.

https://sourceforge.net/p/rusefi/tickets/ lists all the open tickets, some are firmware/C, some are dev console/java. You would probably need at least STMDiscoveryF4 to work on most of them, we can REALLY use software development help

I am OK with fine-pitch SMD soldering. I cheat and use a microscope. Saves the eyes. So, would Frankenso be a good route to go then? I like that it is designed to fit an existing ECM case... will I be able to find one here in the US? What model vehicle is it found in? I recall seeing mention of OBD1 Honda?

OK, I've reviewed the tickets on SourceForge. Is there any prioritization as to what issues are higher priority?

Thanks!

Matthew wrote:So, would Frankenso be a good route to go then? I like that it is designed to fit an existing ECM case... will I be able to find one here in the US? What model vehicle is it found in?

OK, I've reviewed the tickets on SourceForge. Is there any prioritization as to what issues are higher priority?

Mazda Protege 1993 AT, give or take. Also 93 Miata AT probably. For sure available in the US, that's where I get these
Frankenso is the best rusEfi board I am aware of.

I'd say for your first take any open ticket.

Steeper has had good Dev almost working now.

Just got the xtal working. Initial point was the problem.