Re: FW: Help! Asteroids! Please!!!!!!!

REPLACE THE ROM!! Just because the programmer says it's OK
doesn't mean it runs fast enough for the game to work with
it.

Paul Sommers wrote:

>
>
> Gang,
>
> I had trouble with my Asteroids about 2 months ago. The
> screen was blank and
> the watchdog was barking. I did all the usual stuff (even
> caps on both the PCB
> and AR board) and then started searching with a logic
> probe. But the test
> screen was functioning - and it said there were no
> errors?????
>
> I gave up and the machine sat dark until this week when I
> got a dlx board. I
> turned it on to ensure the monitor was still working and
> the game came up!!!!
> Okay!!! The X/Y size was shrunk by about a 1/3 but I
> adjusted that and it was fine.
>
> I played it for about an hour and it went down. Must be
> heat related. Turn to
> the test screen and it is fine. Turn back to the game and
> it is fine again.
> Play for about 30 minutes and black. Turn off for 30
> seconds and turn back on
> and it's fine.
>
> This time after about 30 minutes I started to see a few
> random vectors during
> the game, then a couple of flashes where everything was
> super big, then the
> asteroids were jumping ahead instead of smooth movement.
>
> Switch to test screen and now I'm getting rom errors on
> the F1 rom. Good. Test
> a couple of times more and I get different errors but
> always on the F1 chip.
> Finally, the game went off never to return. Now the self
> test is giving a
> contant FF error on F1 meaning all bits failing.
>
> Check the rom and it's fine.
>
> Replace the socket - no difference.
>
> Check F1 and pin 20 is being held high.
> Check the next rom and same thing.
> Checked third rom and pin 20 is pulsing.
>
> Trace the pin 20's back to the 74139 and they are being
> held high there. Not
> knowing the difference in a stuck bit and a diliberate
> high signal with a
> probe - I replace that chip too. No difference.
>
> Inputs to the 74139 are pulsing all the way back to the
> 6502.
>
> So any ideas now???
>
> The test screen is nice but I'd rather play the game.
>
> As always - all help appreciated.
>
> Cheers
> MacMan
>
> PS: Following my "God life is hard in Australia" I had
> several E-Mails from
> list members offering to hold stuff and ship it to
> Australia. Next week I'll
> investigate getting a Star Wars upright shipped.
>
> It wasn't my intention to post a WTB ANYTHING AT ALL!!!
> Thank you all for your
> generous offers. Looks like I may have already spent my
> Y2K bonus before I get
> it. Happy Y2K - Australia's first and I'll let you know if
> the world ends.
>
> PPS: In New York for the Millenium next year (you know -
> the real one for
> people who can count)

--
Windows:
32 bit graphical interface for a
16 bit patch for an
8 bit operating system written for a
4 bit processor by a
2 bit company that can't stand
1 bit of competition.