Re: vm02: calling all IIcs - Take 2

[Tom Greene <tom@cowgod.org>]

On Aug 29, 7:08 am, David Schmenk <dschm...@YUCH.gmail.com> wrote:
> Tom Greene wrote:
> > On Aug 29, 12:59 am, David Schmenk <dschm...@YUCH.gmail.com> wrote:
> >> Thanks again to Tom for trying this out.  Maybe I can convince him to
> >> try this one out:
>
> >>http://schmenk.is-a-geek.com/tarfiles/VM02ALPHA3.DSK.zip
>
> >> I also discovered a couple of other issues now fixed.  Certain ROM
> >> routines will disable interrupts.  Some of my sample classes that call
> >> ROM routines for low res and hi res graphics all of the sudden stopped
> >> responding to interrupts.  I now re-enable interrupts after every native
> >> method.  I also discovered that my comparison opcodes would adjust the
> >> stack pointer, then compare the values that were now above the stack.
> >> Tsk, tsk.  When an interrupt would occur during the comparison, the
> >> values would get trashed.
>
> >> Glen Bredon wrote a nifty little TSR style program that would hook the
> >> VBL interrupt to keep time.  His notes mentioned problems with various
> >> IIc models.  He actually didn't bother calling the mouse firmware to
> >> service the interrupt on a IIc.  The VBL interrupt would continue
> >> interrupting anyway.  So I now look to see if any hardware claimed the
> >> interrupt.  If not, I assume it's the VBL interrupt.  Hope this works,
>
> >> Dave...
>
> > Sure thing... alas I didn't get any better results, it still runs fine
> > on the IIc+ but freezes on the other two ROMs.
>
> > One thing I notice with both versions is that keyboard input seems to
> > extend the run time a bit. That is to say, if I start the helloworld
> > program and just let it run without touching anything, it runs for
> > about 30 seconds before freezing. If I start the program and then
> > pound on the keyboard continuously, it runs about 35 to 40 seconds.
>
> > Tom
>
> Hi Tom-
>
> Last time you said it continued to buzz after it stopped responding.
> Does it still do this?  I thought I caught all cases, unless the mouse
> firmware is lying about about the VBL interupt source.  Thanks,
>
> Dave...

Yes, the buzz continues. I take it you haven't had this happen on your
own machines?

Tom