MT Displaying TPSADC not TPS% in VE Table when live...

milesinfront · Post by **milesinfront** » Mon Nov 06, 2006 5:07 pm

MS1 - V2.2 - 029t - MT2.25

I'm having trouble getting MT to work in TP% in MegaTune when tuning Alpha-N.

I would prefer to have the TP column of the VE table to be in % (0-100), but when running live on the car, MT is always showing TPADC (0-234).

Has anyone else beaten this problem.

It's no big deal to use TPADC, but if I ever change my TPS I'll have to virtually retune my VE table.

Cheers

Rick

Post by **jsmcortina** » Mon Nov 06, 2006 5:15 pm

TPS% is only used in Megatune, the Megasquirt actually works in TPSADC. With MS1 there is no true "calibrate TPS". So even if you did work in %ages, it would still be a %age of TPSADC.

That's how I remember it - unless someone has figured out a better way for Megatune and MS1 to talk TPS.

James

milesinfront · Post by **milesinfront** » Mon Nov 06, 2006 5:18 pm

Okie Dokie!

I'll train my brain to think in ADC...

Cheers!

Thanks for your prompt reply too!

newtyres1 · Post by **newtyres1** » Thu Nov 09, 2006 12:33 am

I'm pretty sure you can get MT to display in % if you alter the msns-extra.ini file that lives in the Megasquirt/Car1/mtCfg folder on the computer. If you really want to go there, I'll try it on the bench first so I can head you in the right direction instead of a wild goose chase. I've been using tps ADC for 18 months and it's OK, and if you ever change the tps pot you can convert the tps ADC values in the VE table from the old one to the new one with a calculator and a 6-pack (presuming they are of the same linearity). The beauty of running tps ADC is that what you see in MT is exactly what the MS is seeing, so if any errors due to drift or wiring faults arise you will see it very quickly. With alpha-n it is critical that the tps works flawlessly.

Ian.

milesinfront · Post by **milesinfront** » Thu Nov 09, 2006 2:34 am

Sounds great!

I'll wait for your next post....

daxtojeiro · Post by **daxtojeiro** » Thu Nov 09, 2006 12:52 pm

theres a load on Alpha_N in the manuals here:
http://www.msextra.com/manuals/MS_Extra ... htm#alphan

could be of some use to you, it also tells you about it being in ADC, etc,
Phil

newtyres1 · Post by **newtyres1** » Fri Nov 10, 2006 5:11 am

I'm sure it used to be a lot easier a couple of years ago, so maybe this is not the easy way to do it, but it appears to work. Go into C/program files/Megasquirt/Car 1 or whatever your project is named/mtCfg and open up the msns-extra.ini file with notepad or whatever. Do a control + F to find "outputchannels" and change the line

tpsADC = scalar, U08, 7, 1.000, 0.000

to tpsADC = scalar, U08, 7, scale, translate

where scale = 100/(WOT tps ADC - idle tps ADC), and translate = - idle tps ADC

This makes MT display the tps in percent even if the gauge says ADC.

Then to get the VE table to display in tps percent about 3 pages down from the top is a line
#elif tpsBins1 = array, U08, 170, [12], "TPS", scale, translate, 0.000, 255.0, 0.
Drop in the scale and translate numbers from above, and change 255.0 to 100.0

Ian.

Post by **jsmcortina** » Fri Nov 10, 2006 11:19 am

It used to be easier on the face of it, however it was actually incorrect and the Megatune displayed TPS% didn't match the value used in the VE table. The method you propose should work as long as you adjust the .ini file anytime you re-calibrate your TPS.

James

milesinfront · Post by **milesinfront** » Fri Nov 10, 2006 1:31 pm

So what's the consensus?

Does newtyres1's idea seem like the way to go, or stick with ADC?

I think i'll stick with ADC to avoid any screw-ups...

Thanks for your help though!

newtyres1 · Post by **newtyres1** » Fri Nov 10, 2006 4:36 pm

It looked good on the bench with stim, but as James pointed out the downside is that if your tps WOT and idle signals ever change then you'll have to update the ini file to make MT display properly again. If you're worried about messing up the ini file, then save a copy of it first, so you can restore the original file later if required. There is a risk factor involved so if you're not the adventurous type then best to stick with ADC.

Ian.