V6 calibrations, (TCC)

[rr]

Just got back from some tcc testing. This was done with
three bin's (azty based), with minor mods between them.

This testing was aimed at trying to verify the purpose
of two bits at ram location L0034 ($34). The bits are
$10 and $80.

Bin A was stock, used as a baseline.

Bin B had NOP's patched in place of the bit $80 toggles
at $59EF & $59F4.

Bin C had NOP's patched in place of the bit $10 toggles
at $59DD & $59E5.


The first thing I did was to verify operation with the
stock bin. With the scanner and some driving, the lock
and unlock mph's and tps% for unlock changed as the A/C
was turned on & off.

This verifies that the tables shift depending upon the
status of the A/C. In the code @ $5913, it uses L0034,
bit $80 to do this. Hence my labeling of that bit as
the A/C status bit. (Wait, there's more).

It was interesting to note the A/C clutch would cycle on
and off with all three bin's.

With bin B, the tcc would not lock at all. This implies
that bit $80 controls the tcc. But somehow, it is also
effected by the A/C system status.

With bin C, the tcc appeared to respond normally, but
would not table shift when the A/C was turned on. This
is bit $10.

Ram location L0034 is output to the aldl. With the
scanner there are two A/C displays: clutch & request.
The request status appears to follow what is in the code
for L0034, bit $10. I observed the request status at
the same time as the tcc status. From a divabililty
standpoint, this makes sense. As the tcc is locked, the
A/C is dis-engaged. This reduces drivetrain jerk as
the tcc locks.

In conclusion, it appears that bit $10 is used to request
a change in the A/C compressor. To either turn it on
or to turn it off. It it also a request that the A/C
status be returned in bit $80.


(key point here) Bit $80 is used to request that the
tcc be locked. While another routine changes that bit
to signify the state of the A/C compressor back to the
tcc routine. (we have a dual purpose bit).


It is also interesting to note that another bit appears
to be used to signify whether the tcc is locked or not.
This is shown at $5962, ram L0042, bit $08. It is used
to select whether the unlock mph value or the lock mph
value is used.

I want to thank Dan for his input on this. It also gave
me a good reason to get out of the house (test drives!).

BobR.

I was on the lookout for Dopey, but was getting confused
by some of the other drivers as to who he might be.