For better orthogonality, the assembler defines similar symbols as the compiler, depending on the target system selected:
__APPLE2__ - Target system is apple2__APPLE2ENH__ - Target system is apple2enh__ATARI__ - Target system is atari__ATMOS__ - Target system is atmos__BBC__ - Target system is bbc__C128__ - Target system is c128__C16__ - Target system is c16__C64__ - Target system is c64__CBM__ - Target is a Commodore system__CBM510__ - Target system is cbm510__CBM610__ - Target system is cbm610__GEOS__ - Target system is geos__LUNIX__ - Target system is lunix__NES__ - Target system is nes__PET__ - Target system is pet__PLUS4__ - Target system is plus4__SUPERVISION__ - Target system is supervision__VIC20__ - Target system is vic20