Allow VSS recalibration without ECU reset?

Testing and development of Megasquirt 3

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Reverant
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Allow VSS recalibration without ECU reset?

Post by Reverant »

I get this request quite often. People who want to calibrate their VSS ask me to somehow make the recalibration easier by not requiring an ECU reset when the pulses per mile or the full scale speed changes (as it requires you to coast down or switch the ignition off/on while driving which I don't agree with).

Is this possible?
The man behind MS Labs
2005 Audi A3 2.0L TFSI DSG AWD - Extreme MS3
2002 Mazda Miata 1.8 6sp - Enhanced MS3 1.4.0, sequential injection, sequential ignition, big turbo, lots of boost
AbatelliCristian
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Re: Allow VSS recalibration without ECU reset?

Post by AbatelliCristian »

+++++
nathaninwa
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Re: Allow VSS recalibration without ECU reset?

Post by nathaninwa »

I thought this same thing just last week. I needed to drive my race car around the neighborhood and play with tire size to get vss to match for traction control, took 5 trips around the block and multiple stops and refires to get it right

I'm not sure what things require a hard reset, but can there be such a thing as soft reset and when done a final hard reset can be done?
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93supercoupe
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Re: Allow VSS recalibration without ECU reset?

Post by 93supercoupe »

Would be nice to see it not require a hard reset.
BootlegTuned
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Re: Allow VSS recalibration without ECU reset?

Post by Reverant »

I haven't checked the code but I think the reason the reset is necessary is because some form of calculation that is used afterwards is done during the bootup/init phase. It's not done in the main loop afterwards to save CPU time, hence the required reset. The new "Reset button" may help somewhat here but I would really prefer a live calculation.
The man behind MS Labs
2005 Audi A3 2.0L TFSI DSG AWD - Extreme MS3
2002 Mazda Miata 1.8 6sp - Enhanced MS3 1.4.0, sequential injection, sequential ignition, big turbo, lots of boost
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