Changing VSS issues - noob to Arduino/MPGuino
 

Hi guys, first off, I’d like to point out that as an auto electrician I have a strong electrical background and a fairly good understanding of electronics at a component level. But as far as coding goes, I’m a noob. I understand the processes behind LOGIC from relay applications but that’s it. I’m learning though. Enjoying losing my hair while I learn as well! Haha

Anyway... here’s my issue.

Last night I assembled my MPGuino on a breadboard. Using two wire legacy LCD and analog MUX buttons. All goes well! Woohoo!

Except I brought it to work with me with the intentions of trial fitting the breadboard. I don’t have access to a computer to adjust code or anything.

When I attempt to program my VSS to 4000ppm, I can input the numbers just fine but when I confirm the entry, it tells me “Param Changed” but then it just displays a 0 for my VSS.

What gives? What am I doing wrong?

I’m assuming I can modify the sketch to have 4000 as my default VSS when I get home tonight, but thats not the way it supposed to happen right? I should be able program it all from the LCD right?

I haven’t even attempted the injector values as I’m intending to pull my injectors today, rebuild/clean them and get an average flow rate across all six of them.

Edit: I just tried adjusting the VSS to 3999 and this time it accepted the value as 99

No one eh?

This project really is dead in the water now isn’t it?

Maybe the programming is worng and is only expecting a number up to 256...

or maybe it's accepting 4000, but wont display more than the last 2 digits? Perhaps see if everything works despite it.

I didn't consider the 256 potential. But I don't think so as when I got a chance to look at the code, I attempted to change it manually before compiling and uploading and the value I changed was the default 10,000 or something similar. (can't remember but it was a lot higher than 256)

When I powered it up, it showed my VSS value as being "0" again. So I'm tending to lean towards your second suggestion and that it's just displaying the last digit or two.

I can't comment on how accurate it was though... I had a slight "mishap" and I accidentally dropped the 12+VDC wire onto the board as I was plugging it in for a test run... consequently... The UNO board... well... Esta roto!

Thankfully I'd already ordered a four new clones, two Megas and ten Nanos' that I'm just waiting on delivery for so I can resume.

I really would like to see this project supported still. What can I do to help get it back off the ground? I'm assuming it's fallen by the wayside because the cost of the scangauge has dropped drastically with clones also.

But here in Australia, OBD2 wasn't mandated until the 21st century and given that we tend to keep our cars for so much longer than the US does, many of these cars are still on the road today.

I'd be happy to donate, but something tells me, that won't bring the project back to life.