DLX汇编例程

例程一

;add3.s 
; Program begin at symbol main 
; requires module INPUT 
; Load two programs (add3.s and input.s)  
; Note: load add.s first then follow by inputs. 
; Execute, press (F5) 
; read 1 numbers from stdin and add 3 upon it (integer) 
; the result is written to stdout 
;-------------------------------------------------------------------------- 
 
			.data 
Prompt: 	.asciiz         "\nEnter the number(> 1): " 
			.align          2 
StrPtr: 	.space          4 
PrintFt:	.asciiz         "Your number %d+3 = %d" 
			.align          2 
PrintPar:   .word           PrintFt 
Yournumb:   .space          4 
PrintSum:   .space          4 
			.text 
			.global main 
main: 
			addi            r1,r0,Prompt    ;put prompt in arg r1 
			jal             InputUnsigned   ;call subroutine 
			sw              Yournumb,r1     ;store your number 
			addi            r2,r1,3         ;add 3 to your number 
			sw              PrintSum,r2     ;store sum 
			addi            r14,r0,PrintPar ;prepare to print 
			trap  5                         ;print to standard output 
			;**********end************ 
			trap            0

例程二

; 
      ; getchar.s 
      ; 
      ; R1 = getchar(); 
                      .data 
      ReadBuf:        .space          8 
      ReadPar:        .word           0,ReadBuf,4 
      SaveR14:        .space          4 
      SaveR15:        .space          4 
                      .text 
                      .global getchar 
      getchar: 
                      sw      SaveR14, r14            ;save register r14 
                      sw      SaveR14, r15            ;save register r15 
                      addi    r14,r0,ReadPar 
                      trap    3 
                      addi    r15,r0,ReadBuf 
                      lbu     r1,0(r15) 
                      lw      r14, SaveR14 
                      lw      r15, SaveR15 
                      jr      r31                     ;return

例程三

; 
      ; ascii.s 
      ;-------------------------------------------------------------------------- 
 
      ; Program begin at symbol main 
      ; requires module getchar 
      ; print the character ascii code  
      ;-------------------------------------------------------------------------- 
 
                      .data 
      Hello:          .asciiz         "\n\nEnter any char(hit return after that, 
      q to quit): " 
                      .align          2 
      StrPtr:          .space          4 
      PrintFt:         .asciiz         "\nThis char = %c and its ascii value = 
      %d" 
                      .align          2 
      PrintPar:        .word           PrintFt 
      PrintChar:       .space          4 
      PrintVal:        .space          4 
                      .text 
                      .global main 
      main: 
                      addi            r2,r0,Hello 
                      sw              StrPtr,r2 
                      addi            r14,r0,StrPtr 
                      trap  5 
                      jal             getchar 
                      seqi            r3,r1,113 
                      sw              PrintChar(R0),R1 
                      sw              PrintVal(R0),R1 
                      addi            r14,r0,PrintPar 
                      trap            5 
                      beqz            r3,main 
                      ;*** end 
                      trap  0