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[/] [eco32/] [trunk/] [stdalone/] [hello/] [hello.s] - Blame information for rev 64

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;
; hello.s -- Hello, world!
;
 
        .set    tba,0xF0300000          ; terminal base address
        .set    tos,0xC0010000          ; top of stack
 
        ; get some addresses listed in the load map
        .export reset
        .export start
        .export out
        .export hello
 
        ; minimal execution environment
reset:
        add     $29,$0,tos               ; setup stack
        jal     start                   ; do useful work
reset1:
        j       reset1                  ; halt by looping
 
        ; main program
start:
        sub     $29,$29,8               ; create stack frame
        stw     $31,$29,0                ; save return register
        stw     $16,$29,4               ; save register variable
        add     $16,$0,hello             ; pointer to string
loop:
        ldbu    $4,$16,0         ; get char
        beq     $4,$0,stop               ; null - finished
        jal     out                     ; output char
        add     $16,$16,1               ; bump pointer
        j       loop                    ; next char
stop:
        ldw     $31,$29,0                ; restore return register
        ldw     $16,$29,4               ; restore register variable
        add     $29,$29,8               ; release stack frame
        jr      $31                     ; return
 
        ; output a character to the terminal
out:
        add     $8,$0,tba                ; set I/O base address
out1:
        ldw     $9,$8,8                 ; get xmtr status
        and     $9,$9,1                 ; xmtr ready?
        beq     $9,$0,out1               ; no - wait
        stw     $4,$8,12                ; send char
        jr      $31                     ; return
 
        ; a very famous little string...
hello:
        .byte   0x0D, 0x0A
        .byte   "Hello, world!"
        .byte   0x0D, 0x0A
        .byte   0x0D, 0x0A, 0

Line No.	Rev	Author	Line
1	18	hellwig	`;`
2			`; hello.s -- Hello, world!`
3			`;`
4
5			`.set tba,0xF0300000 ; terminal base address`
6			`.set tos,0xC0010000 ; top of stack`
7
8			`; get some addresses listed in the load map`
9			`.export reset`
10			`.export start`
11			`.export out`
12			`.export hello`
13
14			`; minimal execution environment`
15			`reset:`
16			`add $29,$0,tos ; setup stack`
17			`jal start ; do useful work`
18			`reset1:`
19			`j reset1 ; halt by looping`
20
21			`; main program`
22			`start:`
23			`sub $29,$29,8 ; create stack frame`
24			`stw $31,$29,0 ; save return register`
25			`stw $16,$29,4 ; save register variable`
26			`add $16,$0,hello ; pointer to string`
27			`loop:`
28			`ldbu $4,$16,0 ; get char`
29			`beq $4,$0,stop ; null - finished`
30			`jal out ; output char`
31			`add $16,$16,1 ; bump pointer`
32			`j loop ; next char`
33			`stop:`
34			`ldw $31,$29,0 ; restore return register`
35			`ldw $16,$29,4 ; restore register variable`
36			`add $29,$29,8 ; release stack frame`
37			`jr $31 ; return`
38
39			`; output a character to the terminal`
40			`out:`
41			`add $8,$0,tba ; set I/O base address`
42			`out1:`
43			`ldw $9,$8,8 ; get xmtr status`
44			`and $9,$9,1 ; xmtr ready?`
45			`beq $9,$0,out1 ; no - wait`
46			`stw $4,$8,12 ; send char`
47			`jr $31 ; return`
48
49			`; a very famous little string...`
50			`hello:`
51			`.byte 0x0D, 0x0A`
52			`.byte "Hello, world!"`
53			`.byte 0x0D, 0x0A`
54			`.byte 0x0D, 0x0A, 0`

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Subversion Repositories eco32

[/] [eco32/] [trunk/] [stdalone/] [hello/] [hello.s] - Blame information for rev 64