[R0] - 
[R2R1] - 
[R5R4R3] -  (-)

---

 

1587h*63h=85335

01100011*00010101 10000111

-: 0000 1000 0101 0011 0011 0101

DONE

---

 

(-16)*(-666)=8CC4

16  =           0001 0110
666 = 0000 0110 0110 0110

  16h  - 10010110          (96h)
  666h - 10000110 01100110 (8666h)

-: 00000000 10001100 11000100 (8CC4)

DONE