Picture 8 on the web site is *unquestionably* the atmospheric pressure sensor,
as Randy said.
I don't recall off hand what the upright component in picture 6 is, but it ain't
an EPROM.
The three largest chips in pictures 3, 4 and 5 (not the Toshiba ones) are
proprietary chips made by ND for Yamaha. That's the stuff we're really
interested in. There are no on-line resources for looking into these, and I
doubt that they'd be willing to simply tell us what's inside.
The Toshiba chips aren't very interesting. One is a latch, one is a flip-flop
and one is a gate. Standard digital stuff. I identified all the standard
digital and analog chips on the board at one time, and there just isn't anything
particularly fascinating or enlightening.
The long and the short of it, guys, is that THERE ARE NO EPROMS IN THE GTS
ECU!!! No sense trying to find one. EPROMS are VERY easily identified. If
there were one in there, it would stick out like a sore thumb. Either (a) there
is a non-standard ROM/PROM on the board that contains the mappings, or (b) the
"mappings" are hard-wired or burned into the ND chips.
Short of a personal contact at ND or Yamaha with access to such confidential
stuff, we are highly unlikely to sort out on our own how all this works. It is
truley a "black box."
HOWEVER, since the objective is to "transform" a 93 ECU into a 94 ECU, I would
suggest that we compare between ECUs of the two years the IC part numbers on
those three largest chips. Odds are, one or more of them will be different,
with no other changes on the board. If we can find what chips need to be
replaced, perhaps someone can convince Yamaha or ND to cell us some ....
No, I don't believe that for a second.
Yes, I do read minds.
- Bill G.
