Switching manual to auto then odd shifting behaviour

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.
Post Reply
flak monkey
Posts: 50
Joined: Sun Sep 21, 2014 11:28 am

Switching manual to auto then odd shifting behaviour

Post by flak monkey »

Controller is more or less performing OK now - but I have problems with the auto/manual modes.

If I go from auto to manual it works fine, paddles function, everything is good. However strange things happen when I try to go back into auto mode.

Pull both paddles and sometimes it goes into auto fine. However, and this seems to happen if you have been driving for a while and have gone from auto to manual to auto a few times, when you switch back to auto it randomly changes down when it shouldn't soon after going back into auto mode. If you leave it it will change down again.

Rather concerning...

Attached a log showing this happening, starts off in manual, gear 3.

At 21064 I change up manually to 4th.
At 21071 I pull both paddles to go back into auto mode.
At 21072 it changes down to 3rd - no reason, I am above the speed required for 4th in my tables, and low TPS.
At 20173 i go back into manual and 21075 change up to 4th.

This continues to happen until you stop and restart the engine.

I have more than one data log of this happening too - on one occasion I was travelling at around 35mph, switch out of manual to auto and it decides to change down all the way to 1st gear before I realised what was happening and then put it back in manual to change back up.

This isn't helping build any trust....
Attachments
shift2016-05-04_17.46.39.msq
(61.92 KiB) Downloaded 644 times
shift button issue.msl
(513.53 KiB) Downloaded 519 times
flak monkey
Posts: 50
Joined: Sun Sep 21, 2014 11:28 am

Re: Switching manual to auto then odd shifting behaviour

Post by flak monkey »

Just me then :)

I had another corruption of the firmware today for some reason - no idea why, no settings had been changed on the controller for a long time. It left me with 1st and reverse only - managed to limp 5 miles to the nearest store to get some tools to open up the MShift and reload the firmware - just as well I had my laptop in my bag...

Anyway - I'll continue to monitor the auto/manual thing and see if I can spot a pattern to why it happens.
Post Reply