AA80E 8-speed

[Jim Blackwood]

Thanks Lance, I'll upload the entire AA80E document, and then start working on getting the GPIO board, wiring and such. I still have significant parts of the driveline upgrade to complete before testing can begin so I probably won't be ready as soon as you'd like but I'll keep at it. I have other files but they are mostly tear down and inspection.

JB

[Jim Blackwood]

2

[Jim Blackwood]

Last 3 sections.

[Bernard Fife]

Thanks for those. When I get a chance, I will gather together the needed info and put in on a web page here: http://www.msgpio.com/manuals/mshift/AA80E/AA80E.html

Lance.

[Jim Blackwood]

OK. Here is the complete vehicle wiring file. Do you think it would be helpful to include the teardown files, or not worth the trouble?

JB

[Bernard Fife]

JB,

The tear-down docs are probably not needed at this point - unless there we run into something we can't deduce from the other docs. So leave them for now, and when I get the page a little further along we can see what we might be missing.

Lance.

[Jim Blackwood]

OK great! I'll check back in a few days.

JB

[Bernard Fife]

JB,

I have done a quick survey of the docs. The tentative circuit assignments for the GPIO are here:

http://www.msgpio.com/manuals/mshift/AA80E/AA80E.html

However, we need at least one more shift solenoid driver circuit. I am completely happy to add this to the base code, but we need to decide which other circuit(s) to give up. The possibilities are:

1. non-CAN MAP/TPS/MAF, AD5, EGT1, Amp24 - this is the least likely to be used, I suppose, but means the users *must* use CAN and MS2/3, i.e. no standalone if using the additional solenoid driver.
2. One or more of the LED circuits - these are already programmable for the various gears, so no new programming is needed. At very least, this can be used for testing.
3. One or two of the shift lever position inputs, meaning the user would have to use the voltage based inputs (and with 8 forward gears plus PNR there is a fairly small (but workable) range for each gear's selection).

No matter which are used, an add-on driver and flyback component(s) will be required, of course.

Any thoughts?

Lance.

[Matt Cramer]

I would prefer not to use (3) since the factory shifter uses digital inputs instead of analog, so it would be better to keep compatibility with the factory shifter. I would put in a user-selectable option to either use (1) or (2).

[Bernard Fife]

Matt,

Yes, I agree. The voltage based scheme requires a lot more work on the user side to work correctly and reliably (increasingly so as the number of forward speeds goes up). There doesn't need to be an option for 2 though, it is already in place and can be used right now (with hardware mods but no code changes).

The problem with using the LEDs is that then the 7-segment gear display gets tricky. In some cases it may be that one of the solenoid outputs provides an appropriate signal that could be tapped in to, but that doesn't appear to be the case with the AA80E at first glance.

BTW, there is a 4th option: daisy chain a second GPIO, and write a bit of extension code for it to control additional outputs. That does up the cost, though...

Lance.