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Re: Apple Integer BASIC firmware card
- Subject: Re: Apple Integer BASIC firmware card
- From: dempson@actrix.gen.nz (David Empson)
- Date: Sun, 1 Jul 2001 22:42:35 +1200
- Newsgroups: comp.sys.apple2
- Organization: Empsoft
- References: <9h2op4$r7j$1@News.Dal.Ca> <9hmtge$ciq$1@venus.itns.co.za>
- User-agent: MacSOUP/2.4.2
- Xref: archiver1.google.com comp.sys.apple2:9798
Stephen Shaw <xstephenx@apple2.org.za> wrote:
> You can use them to "break" copy protected software. When you flick the switch
> which protrudes out at the back of the card in generates a non maskable
> interrupt (NMI).
You're thinking of a different card, such as a "Wildcard".
With the Integer BASIC firmware card, all the switch does is set the
initial state of the latch which determines whether the card is
overriding ROM when you press Control-Reset.
You can use it to reset into the monitor without any chance of the
software intercepting the reset operation, but this is more intrusive
than an NMI.
With a Wildcard, there is a button attached to the card which generates
an NMI. This is intercepted by firmware on the card, which then does a
memory dump directly to disk.