# fan_demo_fixed.s — corrected to assemble in QtSPIM

.data

FAN_DUTY:  .word 0
FAN_TACH:  .word 0
FAN_CTRL:  .word 0

.text

.globl main
.ent main
main:

        # Set PWM duty to ~50% and enable
        LUI   $t0, 0xFFFF
        ORI   $t0, $t0, 0x0000        # $t0 = FAN_DUTY addr
        ORI   $t1, $zero, 128         # duty = 128
        SW    $t1, 0($t0)

        LUI   $t2, 0xFFFF
        ORI   $t2, $t2, 0x0008        # $t2 = FAN_CTRL addr
        ORI   $t3, $zero, 1           # enable = 1
        SW    $t3, 0($t2)

loop:   LUI   $t4, 0xFFFF
        ORI   $t4, $t4, 0x0004        # tach addr
        LW    $t5, 0($t4)             # read tach_count (optional)
        J     loop
        NOP


        # (Unreachable) exit pattern
        li      $v0, 10
        syscall
.end main