_gf128_mul:
	... rest of routine
                sbc a, a
			.smc_poly:=$+1
                and a, 11100001b
			.smc_read_byte:=$+2
                xor a, (ix - 16)		; little endian
			.smc_write_byte:=$+2
                ld (ix - 16), a


_gf128_mul_set_polyval:
	ld a, 10000111b
	ld (_gf128_mul.smc_poly), a
	ld a, -1
	ld (_gf128_mul.smc_read_byte), a
	ld (_gf128_mul.smc_write_byte), a
	ret

_gf128_mul_reset:
	ld a, 11100001b
	ld (_gf128_mul.smc_poly), a
	ld a, -16
	ld (_gf128_mul.smc_read_byte), a
	ld (_gf128_mul.smc_write_byte), a
	ret