ads103

Hello Miataturbo! ADS103 here - your newest member, looking for getting started advice on the Megasquirt platform. I'll start with a little background. A buddy of mine couldn't get his MSPNP2-MM9697 to work on his '97 Miata. His car would idle, but the moment he blipped the throttle to rev it up, it'd stall. Instead of trying to fix it, he gave me the MSPNP instead after I showed some interest... I became interested after seeing digital gauges like the one Donut Media used in their Money Pit series. Unfortunately, my buddy gave me literally just the MSPNP. No copies of Tuner Studio or any base maps. No IAT sensor or wideband O2 sensor. Not even the little tee for putting a vacuum hose. Just the MSPNP and a promise that it'd work on my '96. With friends like these, who needs enemies, huh?


So far, I've learned that I'll need to plumb the vacuum line and install a wideband O2 sensor at a bare minimum, and that base maps are available from the megasquirt website. And while obtaining them won't be hard, I've actually got questions beyond this basic setup.


Although its been a while, I used to program microcontrollers for hobby projects. The nice thing about an Arduino is, you can set any pin to do arbitrary jobs, from simple logic to generating a PWM signal, to something as complex as serial communication. And while looking at the Miata's ECU wiring harness, I began to wonder if the megasquirt can control more than just fuel and ignition. Note, for instance, that pin 2X on the wiring harness is connected to the evap purge solenoid. And when I partially disassemble my MSPNP2, I can see a copper trace on the circuit board connected to that pin. Unfortunately, I can't fully remove the board without removing the MAP sensor's hose, and that's glued in... The fact that there's a trace there has me wondering, though... Can I make the megasquirt vent my fuel tank through my charcoal canister while I'm cruising? And if it can do that, what other kinds of "boring" tasks can it accomplish? And most importantly, how do I make it do those things?


I haven't been able to spend much time in Tuner Studio yet... I won't even be able to power up my MSPNP2 'till the Spring. But I've noticed that if I open Boost/Advanced -> Programmable On/Off Outputs, I see some ports that resemble GPIO pins on a microcontroller, and I can use boolean logic statements to control them. How do I know which physical pins on the MSPNP2 board these map to?


The MSPNP2 seems to have an extra 16 pin port on it that my Miata's factory harness doesn't have. I'm finding references to this breakout header, but struggling to find information regarding what the header actually does. Is there GPIO available here?


It may seem like I'm putting the horse before the buggy here, but I haven't been this excited about a project in a long time - I can only hope my enthusiasm as a noob is contagious! I want to learn everything there is to learn about this platform, and I'm hoping to learn it without burning up a couple of engines along the way. I suppose my biggest question of all is, what's the right place to take the future questions I'm sure to have as I begin to explore the megasquirt platform?

DNMakinson

iTrader: (3)

You know how to write in paragraphs, so that is a plus.

What problem(s) are you wishing to solve?

What are your plans and goals for your car?

DNM

shuiend

iTrader: (24)

Spend $50 at https://evansperformanceacademy.vhx.tv/ for a month subscription. Watch all the EFI basic and advance videos. Then watch all the MS videos.

ads103

DNM, my long-term plans and goals for my car are straightforward: I want to tinker at whim, learn how the machine works, and enjoy the process. Now, I realize that's extremely vague! I'm leaving my goals very open-ended because, at the end of the day, I'm just here to have fun. In the short term, my goal is to use the Megasquirt I've acquired to replicate the functionality of the factory ECU.

Shuiend, thanks for suggesting evansperformance. I'd heard of them and seen samples of a couple of their videos - I may very well pull the trigger and buy their content. I'm also planning on getting some I've seen recommended around the 'net.

Currently, all my questions revolve around the programmable inputs/outputs. I've found some documentation discussing them, as well as other forum posts, but my biggest question seems like such an elusive one... How do I know where these named ports are exposed? Which physical interface exposes a given name? On the other end of the same question, this forum post discusses eight breakout header pins, but it doesn't provide a source for where its quote comes from. I'm fairly confident this isn't discussing the 26-pin option header next to the serial port on the other side of the Megasquirt, too.... So how would I go about addressing these pins?

If these questions are already answered in documentation, I can only apologize - the previous owner of my MSPNP2 didn't give me a manual, and I'm struggling to find this info online.

shuiend

iTrader: (24)

Skip the books. Go straight to Evans videos. His videos are by far a step above anything else out there.