Question

I can run the emulator(s) (x)mips and mars but I don’t know how to make programs. There is no “getting started” for MIPS assembly emulation. Could you sho my a simple program that I just put in the box and run?

Answer 1

Here is code to switch the value of $t0 and $1, and $t2 and $t3. Paste it in a file swap.s using any editor and open the file with the simulator (mars, pcspim, qtspim).

    .text
    .globl main
main:
    li  $t0, -10
    li  $t1, -31
    li  $t2, -10
    li  $t3, -31

    #swap

    xor $t0, $t0, $t1
    xor $t1, $t0, $t1
    xor $t0, $t0, $t1

    addu    $t2, $t2, $t3
    subu    $t3, $t2, $t3
    subu    $t2, $t2, $t3

    li  $v0, 10
    syscall

You always write:

.text
.globl main
main:

#code here

li  $v0, 10
syscall

and go on from there.