Re: VSM troubleshooting, Asteroids

Vector Generator Program Counter

Yes I had an issue with this on a board too, turned out to be a bad 74LS367,
a logic comparator found this but I was trying to find the problem with the
670s & 193s as I new the program counter wasn't working properly....

Scale is an output of DDMA7-DDM4 clocked by !LATCH3 + !LATCH0 * !ALPHANUM

So round & round we go, if the 74LS42 Decoder could be removed & controlled
then I could step thru various chips of the state machine one at a time?

Kev

> Not having any of that in front of me.. ;-) I should have said
> the vector
> state stack... Top left hand side of the schecmatic... Darn,
> can't remember
> what it was 'offically labeled'. Yeah thats it, loaded the ram ok
> and the stack had
> the offests into ram. If the pattern was all localized, the stack
> never got full enought
> to excersie it. So in game mode it would die, in test mode it was
> fine..
>
> Also the the whole thing needed to excersize the Scale0-3 as
> well.
>
> TomW
>
>
> >
> >
> > So the 9010A didn't catch the Vector Ram failure?
> >
> > Curiosity forced me to pull the schematics, the RAM
> > failure should be caught
> > by the 9010A, unless you have a problem with one of
> > the 273 latches
> > (right?).
> >
> > The 3 signals that didn't work properly for me using
> > the Flukescript were
> >
> > !OPTS
> > !SINP0
> > !SINP1
> >
> >
> > Kev
> >
> > > It puts a medium sized PLUS on the screen. I jumper
> > the watchdog
> > > and let if fly. I was going to put scope patterns in
> > a doc for
> > > the various test points during the draw but never
> > got around to
> > > it. What I'd like to do is increase the scaling, and
> > have the vsm
> > > code put in three different places in the vsm ram.
> > I've run into
> > > a few cases that it ran fine, but only because it
> > was located low
> > > in the vsm ram (its such a small pgm it does not
> > fully test the
> > > vsm address space). The game would die, but the vsm was fine.
> > > Turns out that one of the high order bits (I forget
> > the chip) was
> > > out in the vsm ram. So to make this run in low vsm
> > and then again
> > > in high vsm memory space would be nice. Did anyone
> > ever document
> > > the vsm command structure ? That would be helpfull,
> > this PLUS is
> > > from the atari catbox documentation and I just
> > adapted the tests
> > > to the 9010. On of these day's I'll make it pretty..
> > >
> > > TomW
> >
> >
> > -------------------------------------------------------
> > --------------------
> > ** To UNSUBSCRIBE from vectorlist, send a message with
> > "UNSUBSCRIBE" in the
> > ** message body to vectorlist-request@synthcom.com.
> > Please direct other
> > ** questions, comments, or problems to neil@synthcom.com.
> >
>
> --------------------------------------------------------------------------
-
> ** To UNSUBSCRIBE from vectorlist, send a message with "UNSUBSCRIBE" in
the
> ** message body to vectorlist-request@synthcom.com. Please direct other
> ** questions, comments, or problems to neil@synthcom.com.

---------------------------------------------------------------------------
** To UNSUBSCRIBE from vectorlist, send a message with "UNSUBSCRIBE" in the
** message body to vectorlist-request@synthcom.com. Please direct other
** questions, comments, or problems to neil@synthcom.com.
Received on Tue Feb 12 14:54:26 2002