How to crash apple][

There was/is a bunch of memory around 0xC000(or $C000 in the old money)that was used to toggle bits that control memory bank,speaker,graphics mode etc
by just dumping(reading) this range the box crashes(unless you have stuff loaded into the other 64kb bank)

Category:

Science & Technology

Tags:

• apple2
• monitor

[ueberRegenbogen]

You haven't crashed it. You've just left it showing you text page 2 after ploughing through the C05x range. (You also cycled through the graphics modes along the way.) Enter C054 to switch back to page 1.

[xmlisnotaprotocol]

Memory bank(last 16k of addr space)toggle is in the $Cxyz range too so by reading it the 6502 switched out of mon ROM and into uninitialised ram of the lang card(not valid code)

I can load applesoftFP BASIC into the card & see what happens-probably the same( hang)as the program counter would start somewhere in the 16k block-same address that it was in ROM.A reset would re read the reset vector & get back on track(if the 16k lang card was loaded)

[bravo3000pirate]

well, you have more video's so you probably have a camera

[xmlisnotaprotocol]

ok thanks

[bravo3000pirate]

you crashed an emulator....

[xmlisnotaprotocol]

also works on real thing - I cant record video from my real apple ][

[MsHUGSaLOT]

wow how boring.

[Akira625]

When scrolling  through that memory area, you'll also here a pop form the speaker, because $C030 controls the speaker.

[Akira625]

I think I've done that a couple of times while messing around in the Monitor.

[ueberRegenbogen]

Oops. "Reading the The Language Card RAM switch locations", that is.

[ueberRegenbogen]

Reading the The Language Card RAM doesn't do anything; they require writing. Though other cards might do odd things (e.g. leave drive 2 spinning).

Except under ProDOS (which lives up there), copying ROM to LC RAM, then switching in the RAM will go down without a hitch, as you're switching in identical contents. (Applesoft's PC, etc are on zero-page, so are unaffected.). Then you can have fun molesting the copy the firmware in RAM, for amusement. ;)

A hard reset will always enable ROM.