Which 'load' is used in the PC calculations?

A forum for discussing applications and implementations of the MegaShift transmission controller code for the GPIO from B&G. This can control up to 8-speeds and 6 shift solenoids (plus a 16x9 table for controlling a PWM line pressure valve). It has manual and fully automatic modes (16x9 load x speed table), with under and over rev-limit protection, and full data logging of all inputs and outputs (among many other abilities). A TransStim to test your completed board is also available.
Bernard Fife
Posts: 1696
Joined: Fri Apr 04, 2008 1:28 pm

Re: Which 'load' is used in the PC calculations?

Post by Bernard Fife »

Addicted,

That's what it does, but not the way it is intended to work and this is probably an artifact from some other code function. I will fix this and post code here.

Lance.
"Never wrestle with pigs. You both get dirty and the pig likes it." - George Bernard Shaw
Bernard Fife
Posts: 1696
Joined: Fri Apr 04, 2008 1:28 pm

Re: Which 'load' is used in the PC calculations?

Post by Bernard Fife »

Martin,

This 5.100i code should help:
Monitor_5100i.abs.s19
(83.27 KiB) Downloaded 559 times
GPIO_MShift_5100.ini
(285.05 KiB) Downloaded 545 times
There were two issues:
- a parameter (LPshiftOptn) wasn't exposed in the INI that tells the controller what to do with the line pressure when shifting ("Use Table", "Use OFF Value", "Use Shift Limits" that can be found under 'Spare Ports -> Spare Port 3 PWM Setup -> Shift PWM Option'), and
- there was an issue in the code not recognizing this parameter properly.

The attached files fix both (subject to further testing, of course).

Lance.
"Never wrestle with pigs. You both get dirty and the pig likes it." - George Bernard Shaw
Bernard Fife
Posts: 1696
Joined: Fri Apr 04, 2008 1:28 pm

Re: Which 'load' is used in the PC calculations?

Post by Bernard Fife »

Addicted,

Attached is better code. I realize you have other issues to sort at the moment, but I wanted to post this here as I know others are following this thread.
Monitor_5100ii.abs.s19
(83.08 KiB) Downloaded 550 times
GPIO_MShift_5100.ini
(285.05 KiB) Downloaded 552 times
This code has some subtle improvements to the spare port three PWM option logic during a shift, and some changes to the INI. This code will likely be released as 5.101 before too long.

Lance.
"Never wrestle with pigs. You both get dirty and the pig likes it." - George Bernard Shaw
Addicted
Posts: 188
Joined: Mon Oct 14, 2013 7:14 am
Location: Winchester, England

Re: Which 'load' is used in the PC calculations?

Post by Addicted »

Morning Lance,

Well the 5.100i was tested and found to be OK last night. Rather than Sp3% dropping to zero on shift it appears to 'follow table' (despite me not having that option selected!) :) but maybe thats what you are referring to with 5.100ii

I've checked out my solenoids/wiring and they're all spot on at 70ohms for on/off and 5.5ohms for the PC solenoid (I was hoping to find a duff solenoid or something shorted to ground)
Ive ordered a fluid and filter kit for the transmission as thats pretty much all I can do before I'm meant to leave on my trip, if after 18 months sorting the megasquirt/megashift setup I suffer a mechanical failure of the transmission I may well torch the car! :x

I'll load up 5.100ii this afternoon when I finish work.
Bernard Fife
Posts: 1696
Joined: Fri Apr 04, 2008 1:28 pm

Re: Which 'load' is used in the PC calculations?

Post by Bernard Fife »

maybe that's what you are referring to with 5.100ii
Addicted,

Yes. This ought to work correctly with the 5.100ii code, it does on my bench.

I feel you pain about your trans issues; this must be very frustrating after all your careful preparations.

Lance.
"Never wrestle with pigs. You both get dirty and the pig likes it." - George Bernard Shaw
Addicted
Posts: 188
Joined: Mon Oct 14, 2013 7:14 am
Location: Winchester, England

Re: Which 'load' is used in the PC calculations?

Post by Addicted »

Hi Lance, no issues found with 5.100ii
Bernard Fife
Posts: 1696
Joined: Fri Apr 04, 2008 1:28 pm

Re: Which 'load' is used in the PC calculations?

Post by Bernard Fife »

Great, thanks for letting me know!
"Never wrestle with pigs. You both get dirty and the pig likes it." - George Bernard Shaw
Post Reply