Subversion Repositories eco32

;

; hello.s -- Hello, world!

;

; $11  I/O base address

; $12  temporary value

; $13  character

; $14  pointer to string

; $29 stack pointer

; $31 return address

        .set    tba,0xF0300000

reset:  add     $29,$0,0xC0010000

        jal     start

reset1: j       reset1

start:  sub     $29,$29,4       ; save return register

        stw     $31,$29,0

        add     $11,$0,tba       ; set I/O base address

        add     $14,$0,hello     ; pointer to string

        or      $14,$14,hello

loop:   ldbu    $13,$14,0        ; get char

        beq     $13,$0,stop      ; null - finished

        jal     out             ; output char

        add     $14,$14,1       ; bump pointer

        j       loop            ; next char

stop:   ldw     $31,$29,0        ; restore return register

        add     $29,$29,4

        jr      $31             ; return

out:    ldw     $12,$11,8       ; get status

        and     $12,$12,1       ; xmtr ready?

        beq     $12,$0,out       ; no - wait

        stw     $13,$11,12      ; send char

        jr      $31             ; return

hello:  .byte   "Hello, world!"

        .byte   0x0D, 0x0A, 0