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3

This is a little tricky to answer, because only about 30% of a DOS 3.3 boot sector is actually boot code. The BOOT0 ROM has everything needed to read a sector from track 0, so BOOT1 (T0/S0) just needs to call it with physical sector numbers and buffer addresses to load the full RWTS. The DOS INIT command needs a T0/S0 image handy when formatting a disk, so ...


4

Emulators should emulate the Disk ][ hardware at a low level, or they're going to have a bad time. Attempting to pull in the right set of sectors will work for standard DOS or ProDOS disks, but won't work for anything custom. You can find a commented disassembly of the boot ROM here and a "typical" T0/S0 here. You'll note there's a sector ...


0

The PC Transporter provides composite out via a cable run to the internal video header of the Apple II. This could be a missconception. The Apple II does not have a Video-In. The 4 pin connector right of Slot 7 provides the NTSC signal and is in general meant to augment it, like with a PAL converter for European TV. Your intention is simply to use the Apple'...


2

Partial answer: Having looked at the manual, the only connection is a two-wire cable to video aux. They also say that any composite monitor connected to the internal Apple video must be NTSC composite compatible. As the Apple 6502 keeps running, I would assume they have the Apple display a black screen, and then sync up and overlay their own pixel outputs on ...


1

This answer is still a work in progress... A Unix emulator named "Apple //e Emulator" by Randy Frank (aka "apple2e" or just "ap2e" in filenames) goes right back to 1990. It used ProDOS order for both ProDOS and DOS 3.3 disk images! DOS 3.3: Note: the UNIX files contain all the data on a DOS 3.3 5.25 disk. However, the files ...


4

In 2014 I installed a 65CE02 (removed from an Amiga A2232 serial card) into an Apple IIe, for the purpose of confirming the bug in the 65CE02 decimal subtract, said bug having been discovered by Pavel Zima by reverse-engineering of the chip layout. In general the 65CE02 worked fine in the Apple IIe, but any speedup due to some instructions taking fewer clock ...


3

For the cracked version the problem was identified long ago: I have heard that it is only the cracked version of Karateka which has a problem. The problem is that on every disk access, Karateka takes a copy of the ROM from the Disk II controller card and patches it. It then uses the patched copy to do the disk I/O. The resulting code crashes ...


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