Re: Apple II (rev1) instability...HELP!

[Nama <forums6000@mac.com>]

On Apr 7, 2:57 pm, Nama <forums6...@mac.com> wrote:
> Hi all,
> Me again.
> I've recently sold one of my Apple II, and I am moving all my cards
> over to another rev1 Apple II that I own.
>
> I'm trying to find out why this system works fine 90% of the time,
> while the other 10% it crashes and hangs or just displays odd
> behavior.
>
> Setup is as follows and is identical to my previous machine:
>
> 0 - Ram card
> 1 - CFFA #2 ( (prodos 1.1.1 / contiki))
> 2 - SSC
> 3 - empty
> 4 - Uthernet
> 5 - Echo 2
> 6 - Floppy I/O
> 7 - CFFA #1 (turnkey startup to DOSmaster 1.7)
>
> Of course I have tried the system with minimal cards and it still
> exhibits weirdness.
>
> Symptoms:
> -Sometimes hangs on boot.
> -Strange inverted period often seen in top left corner when booting
> from CFFA #1
> -Sometimes craches to the monitor
> -Doing a IN#1 to launch the CFFA #2 always hangs with a strange
> flashing inverted period in the top left corner. often with corrupted
> type on the prodos launch screen.
> -Once it up and running it's usually fairly stable unless I reboot.
> -Have run a looping game for many hours with no problem, but crashed
> to monitor as soon as I restart.
>
> What I have done:
> Tried a new set of ROMs
> Run Apple test utils on the RAM and ROM...no problems found.
> Run the machine from a known good IIe power supply.
>
> If anyone here can shed some light on my problems, I would be very
> grateful. I'm hoping the inverted period may be a good clue to whats
> happening.
>
> I've uploaded some bad photos here if this helps at all:
>
> http://web.me.com/lord_philip/apple_1_%26_II/rev1.html
>
> Much thanks in advance.
>
> Phil

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