you are moving a "long" in the first example, and only using the last word of the long, so if your long value is 0x12345678, you are moving 0x5678
in the second example you move the first word of the argument, so you are moving 0x1234
if you want to move 0x5678 you must add 2 to a7 pointer
move.w _ARGS+2(a7),0x401ffe