Difference between revisions of "Assembly Language Multiplication"
| Line 2: | Line 2: | ||
2 INP R1,2 | 2 INP R1,2 | ||
3 MOV R2,#0 | 3 MOV R2,#0 | ||
| − | 4 LOOP: ADD R2,R2,R0 | + | 4 LOOP:ADD R2,R2,R0 |
5 SUB R1,R1,#1 | 5 SUB R1,R1,#1 | ||
6 CMP R1,#0 | 6 CMP R1,#0 | ||
7 BGT LOOP | 7 BGT LOOP | ||
8 B END | 8 B END | ||
| − | 9 END: | + | 9 END: OUT R2,4 |
10 HALT | 10 HALT | ||
Revision as of 09:04, 14 January 2019
1 INP R0,2 2 INP R1,2 3 MOV R2,#0 4 LOOP:ADD R2,R2,R0 5 SUB R1,R1,#1 6 CMP R1,#0 7 BGT LOOP 8 B END 9 END: OUT R2,4 10 HALT
Line 1 & 2 will get the two numbers to multiply.
Line 3 will make sure register 2 is already set to zero.
Line 4 contains the label to branch back to, it will also add the second number to the value already in register 2
Line 5 will minus 1 from the second number, so we know how many times to run the loop.
Line 6 compares the value in register 1 with zero.
Line 7 if the compare result is greater than, we branch to the loop label.
Line 8 will only be reached if the branch greater than above is false. This line just branches to the end.
Line 9 is the end label and will also output the answer of the multiplication.
Line 10 will halt.
