68000 (MC68000, 68K),
a 16/32-bit CISC microprocessor designed and marketed by Freescale Semiconductor since 1979, started as a division of Motorola. It was used in Atari ST, Commodore Amiga, and Apple Macintosh personal computers, as well in Sun-1 workstations and many dedicated chess computers. 68000 has an external 16-bit data bus and 24 external address lines to index 16 MByte of physical memory, eight 32-bit general-purpose data registers (D0-D7), and eight address registers (A0-A7). The last address register was also the standard stack pointer, and could be called either A7 or SP . Despite different data- and address registers, 68000 was known for its orthogonal instruction set . Like its 8-bit predecessor 6800, but opposed to x86, 68000 is a Big-endian machine.
- MOTOROLA M68000 FAMILY - Programmer’s Reference Manual (pdf)
- 68000 Assembler - User's Manual (pdf) by Paul McKee
- Motorola 68000 from Wikipedia
- Motorola 68000 family from Wikipedia
- 68000 Assembly - Wikibooks
- Rookie 1.0 68000 assembly source, search.s from Index of /rookie/nostalgia/v1