This is a multi-CPU macro assembler for many major 8-bit and 16-bit CPUs
which can assemble code for multiple CPUs in the same source file.

Current CPUs supported:

 * RCA 1802
 * MOS Technology 6502, 65C02 and 6502 with undocumented instructions
 * WDC 65816 (lacks some addressing mode support)
 * Motorola 6809
 * Motorola 6800/6801/68HC11 and Hitachi 6303
 * Motorola 6805/68HSC08
 * Motorola 68HC16
 * Motorola 68000/68010
 * Intel 8051
 * Intel 8080, 8085, and 8085 with undocumented instructions
 * Fairchild F8
 * Atari Jaguar "Tom" and "Jerry" coprocessors
 * Zilog Z-80 and Nintendo Gameboy Z-80 variant 

WWW: http://xi6.com/projects/asmx/