Assembler for MC6809, HD6309, and other vintage CPUs
GPL-3.0 License
Motorola 68000 emulator and disassembler library.
web-based IDE for 8-bit programming and Verilog development
The famous Intel 8080 CP/M 2.2 to Intel 8086/8088 MS-DOS assembly language translator.
The development kit for over a hundred z80 family machines - c compiler, assembler, linker, libra...
cc65 - a freeware C compiler for 6502 based systems
Motorola 68000 assembler, clone of SN 68k (A.K.A. asm68k).