nand2/04_Machine_Language/mult.asm

// mult.asm
// calculate R2 = R0 * R1
// and check the result.

// Load test data: R0 = 13, R1 = 55, R2 = 42
// and set LED to 01 (nothing calculated yet!)
@13
D=A
@R0
MD=D
@DEBUG0
M=D

@55
D=A
@R1
MD=D
@DEBUG1
M=D

@42
D=A
@R2
MD=D
@DEBUG2
M=D

@LED
M=1

// Put your code here:


@R2
M=0
@DEBUG2
M=0
@itr
M=0

// loop declaration
// D = R1 - itr
// if 0 jump to @STOP
// else continue
    (LOOP)
@itr
D=M
@R0
D=M-D
@DEBUG0
M=D
@END
D;JEQ

// R2 = R0 + R2
// itr = itr + 1
@R1
D=M
@R2
DM=D+M
@DEBUG2
M=D
@itr
M=M+1

// back to loop declaration
@LOOP
0;JMP

// till here!

// Check result according to
// LED = 2 (correct result)
// LED = 3 (wrong result)
// and HALT
(END)
@R2
D=M
@715
D=D-A
@OK
D;JEQ

(NOK)
@3
D=A
@LED
M=D
@HALT
0;JMP

(OK)
@2
D=A
@LED
M=D

(HALT)
@HALT
0;JMP