.TAS6LDAXX15; Reverse the sign of the x-coordinate of the vector inEOR#%10000000; XX15STAXX15LDAXX15+1; Then reverse the sign of the y-coordinateEOR#%10000000STAXX15+1LDAXX15+2; And then the z-coordinate, so now the XX15 vector isEOR#%10000000; pointing in the opposite directionSTAXX15+2RTS; Return from the subroutine