one selective clutch for upshift, one for downshift

[Addicted]

Lance,
Through datalogging the Bosch TCU attached to my Audi 097 transmission I've found that it has one solenoid thats activated for all shifts (upshift and downshift), but also a second one that only operates on either downshift or when engaging TCC (not on upshift).

I've studied the code but cannot see any way of implementing this. Can you confirm if this is/isn't possible?

Thanks

[Bernard Fife]

Addicted,

If I understand correctly, you might be able to use the selective clutch function of the spare ports.

See:

http://www.msgpio.com/manuals/mshift/V41tune.html#hh

and:

http://www.msgpio.com/manuals/mshift/spareport.html

and:


http://www.msgpio.com/manuals/mshift/V41tune.html#sf


You can wire a device to both a spare port and TCC to AND them together.

Lance.

[Addicted]

Thanks Lance... either my head is full or there's some contradictory information (depending on code)..

I thought I needed to use output 5 (PAD01) for my TCC.. but there's reference to PT3 being used for TCC, but I cannot find any other reference to PT3 as TCC.

If I do use PT3 for TCC then I won't need to use output 5 or output 6 at all...

Output 1 - Shift Solenoid 1
Output 2 - Shift Solenoid 2
Output 3 - Shift Solenoid 3
Output 4 - AKA Spare 2 - Selective clutch on all shifts
Output 5 - not used
Output 6 - not used
Output 7 - AKA Spare 1 - Selective clutch on downshift
Output 8 - AKA Spare 0 - Speedo output
Output 9 - AKA Spare 3 - Line pressure PWM

What am I missing? where is TCC?

[Bernard Fife]

Addicted,

ANY of the spare ports can be used in TCC mode in recent codes. See: http://www.msgpio.com/manuals/mshift/spareport.html

However, the default TCC output is tied to processor pin PT3. PT3 has no other function, not even as a spare port (which is why it isn't listed on the spare port page). It is not listed as an "OutputX" because the 'output' label has been restricted to pins that can be used as shift solenoid outputs. So yes, you can use PT3 for TCC control.

PAD01 is used as shift lever Input2 as a default, but can also be used as Output5 (with circuit modifications of course) which in turn can be used in TCC mode. Output6 is normally used for the third input for a digital shift lever. If you have a digital shift lever signal on multiple pins, you will need to use these for that. If you have a voltage based shift lever input signal, you don't need to use these inputs. There is more here: http://www.msgpio.com/manuals/mshift/V41tune.html#il

The default pin assignments are shown in a table here: http://www.msgpio.com/manuals/mshift/assembly.html

I hope that is clearer, but if it isn't let me know I I'll try to explain better.

Lance.

[Addicted]

Clear as mud Lance

I think I've got it now. Its strange, I've been 'doing' megasquirt since the early days and have done plenty of installs without issue, but for some reason I'm stuggling with Megashift documentation.






Sharing my home with my newborn daughter may be a contributing factor however...


Again, thanks Lance

[Bernard Fife]

Addicted,

This *might* help clear thing up a bit: http://www.msgpio.com/manuals/mshift/portspins.html

Many congratulations on the newborn! In time you will get used to the lack of sleep (if only because you will have to...).

Lance.

[Addicted]

Hello again Lance

Honestly this is my last query... honestly..

Regarding the selective clutch with TCC lockup.. I just cannot see how I can do this.

Looking at my datalogs, TCC only engages in third, and when it does the 'downshift' clutch is activated (briefly). But I don't see any 'trigger' within the software that will allow this to happen..

In fourth TCC is always engaged 100% of the time, non of my datalogs show TCC disengage in fourth, it simply downshifts to third (sometimes with TCC still engaged!)

So shifts are always: 1 - 2 - 3 - 3TCC - 4TCC - 3TCC - 3 - 2 - 1 or occasionally 1 -2 - 3 - 3TCC - 4TCC - 3 - 2 - 1

Can you think of any way of activating the 'downshift' clutch (SP1/output 7) just as TCC locks up?

I half considered setting it up as a 5 speed box, calling 3TCC fourth (and fourth, fifth), that way I can activate Spare Port 1 on upshift between third and fourth and then fourth to fifth... does that make sense?

[Addicted]

I'm thinking of trying a Schmidt trigger and a transistor to link the tcc to the downshift solenoid..

Alternatively I have an Arduino pro mini in there controlling my gear display, that has some spare ports available, so it would be easy to do in software..