Create your own Version of Microsoft BASIC for 6502
Update: The source is available at github.com/mist64/msbasic
6502
"ROR" in Microsoft BASIC for 6502
If you disassemble any version of Microsoft BASIC for 6502, you’ll find this code in a function that normalizes the (simulated) floating point accumulator:
Bill Gates’ Personal Easter Eggs in 8 Bit BASIC
If you type “WAIT6502,1” into a Commodore PET with BASIC V2 (1979), it will show the string “MICROSOFT!” at the top left corner of the screen. Legend has it Bill Gates himself inserted this easter egg “after he had had an argument with Commodore founder Jack Tramiel”, “just in case Commodore ever tried to claim that the code wasn’t from Microsoft”.
How MOS 6502 Illegal Opcodes really work
The original NMOS version of the MOS 6502, used in computers like the Commodore 64, the Apple II and the Nintendo Entertainment System (NES), is well-known for its illegal opcodes: Out of 256 possible opcodes, 151 are defined by the architecture, but many of the remaining 105 undefined opcodes do useful things.
Optimized Flags Code for 6502
When I disassembled Steve Wozniak’s Apple I BASIC, I found a 6502 trick that I had never seen before, although I had read a lot of 6502 code, including the very well-written Commodore BASIC (i.e. Microsoft BASIC for 6502).
1200 Baud Archeology: Reconstructing Apple I BASIC from a Cassette Tape
The audio file that was posted two weeks ago is indeed a very important artifact of computer history: It is a recording of the “Apple I BASIC” cassette tape that came with the Apple I. It is the first piece of Software ever sold by Apple (not counting computer firmware).
Tool’s ‘Rosetta Stoned’ Live Performance to Include Apple I Schematic
It probably takes a geek in the front row (which is likely for a concert in San Francisco) to notice that the computer schematics Tool showed on the screens during their âRosetta Stonedâ performance are those of an Apple 1 – but distorted: