Microsquirt 951

[Tom]

Hey Tom, completely off topic, but I was doing some reading and internet searches and noticed you got the factory boost gauge working with a Arduino, you wouldn’t happen to have a link sharing that build and the code would ya? I’d like to get mine running and have a spare Arduino sitting here

https://carpokes.com/viewtopic.php?t=68

viewtopic.php?t=267

I have on my list to make a couple of these in the next week or two. If you want one, let me know. I ended up making my own circuit board (not an Arduino per se), with supporting components to drive the gauge, so not sure my code would work on an actual arduino. I can dig all that up and walk you through making something work on an Arduino if you'd rather DIY. If memory serves I added a voltage follower to the MAP input, and low-pass filter on the cpu's PWM signal, and a voltage divider (in effect) on the output. I'd have to pull up the schematic to remember the specifics. With all that in place, the software is pretty simple -- it's just a loop that samples the MAP sensor input and converts it to a PSI value based on the MAP sensor voltage scale formula (which varies by sensor), and then converts that to the appropriate output voltage to show that PSI on the factory gauge (the formula for which I derived myself after mapping various voltages to gauge readings).

edit: adding the speedometer calibrator increased the code complexity a lot, since it has to do all of the above at the same time it sending the speedometer up to ~300 pulses per second at specific intervals....

[DGUN951]

Hey Tom, completely off topic, but I was doing some reading and internet searches and noticed you got the factory boost gauge working with a Arduino, you wouldn’t happen to have a link sharing that build and the code would ya? I’d like to get mine running and have a spare Arduino sitting here

https://carpokes.com/viewtopic.php?t=68

viewtopic.php?t=267

I have on my list to make a couple of these in the next week or two. If you want one, let me know. I ended up making my own circuit board (not an Arduino per se), with supporting components to drive the gauge, so not sure my code would work on an actual arduino. I can dig all that up and walk you through making something work on an Arduino if you'd rather DIY. If memory serves I added a voltage follower to the MAP input, and low-pass filter on the cpu's PWM signal, and a voltage divider (in effect) on the output. I'd have to pull up the schematic to remember the specifics. With all that in place, the software is pretty simple -- it's just a loop that samples the MAP sensor input and converts it to a PSI value based on the MAP sensor voltage scale formula (which varies by sensor), and then converts that to the appropriate output voltage to show that PSI on the factory gauge (the formula for which I derived myself after mapping various voltages to gauge readings).

edit: adding the speedometer calibrator increased the code complexity a lot, since it has to do all of the above at the same time it sending the speedometer up to ~300 pulses per second at specific intervals....

Tom, thats awesome!!!! How much do they go for?

[Tom]

Hey Tom, completely off topic, but I was doing some reading and internet searches and noticed you got the factory boost gauge working with a Arduino, you wouldn’t happen to have a link sharing that build and the code would ya? I’d like to get mine running and have a spare Arduino sitting here

https://carpokes.com/viewtopic.php?t=68

viewtopic.php?t=267

I have on my list to make a couple of these in the next week or two. If you want one, let me know. I ended up making my own circuit board (not an Arduino per se), with supporting components to drive the gauge, so not sure my code would work on an actual arduino. I can dig all that up and walk you through making something work on an Arduino if you'd rather DIY. If memory serves I added a voltage follower to the MAP input, and low-pass filter on the cpu's PWM signal, and a voltage divider (in effect) on the output. I'd have to pull up the schematic to remember the specifics. With all that in place, the software is pretty simple -- it's just a loop that samples the MAP sensor input and converts it to a PSI value based on the MAP sensor voltage scale formula (which varies by sensor), and then converts that to the appropriate output voltage to show that PSI on the factory gauge (the formula for which I derived myself after mapping various voltages to gauge readings).

edit: adding the speedometer calibrator increased the code complexity a lot, since it has to do all of the above at the same time it sending the speedometer up to ~300 pulses per second at specific intervals....

Tom, thats awesome!!!! How much do they go for?

I've been charging $100 plus $9 shipping for Carpokes members. I had the circuit board professionally/machine assembled, so just trying to recover costs for the most part.

[fasterfaster]

Haven’t posted in a while, just wanted to follow up on my project, over the winter I finish swapping over to a microsquirt stand-alone and coil on plug setup. Got her running over the weekend, so far I’m on my 4th revision of the tune, running 17.5psi goal is to eventually bring it to 25psi. Like I was running on M-tune…. Micro squirt is in the megasquirt family. I’m running waste spark with hyabusa stick coils and Batch fuel inejection. So far so good, Tuner studio and mega log viewer have been awesome for tuning software.

Great work. What trigger wheel, position sensor, and sensor holder are you running?

[nick_968]

Hi Tom I might be interested in this circuit board if it allows the boost gauge on the 944 tacho to work from a map sensor input or a Motec/ standalone output? I have always wanted to have the tacho/ boost combo on my 968 8v turbo if indeed this is possible.