Data commit

Task/User-input-Text/ARM-Assembly/user-input-text.arm

@@ -0,0 +1,149 @@
+/* ARM assembly Raspberry PI  */
+/*  program inputText.s   */
+
+/* Constantes    */
+.equ BUFFERSIZE,   100
+.equ STDIN,  0     @ Linux input console
+.equ STDOUT, 1     @ Linux output console
+.equ EXIT,   1     @ Linux syscall
+.equ READ,   3     @ Linux syscall
+.equ WRITE,  4     @ Linux syscall
+/* Initialized data */
+.data
+szMessDeb: .asciz "Enter text : \n"
+szMessNum: .asciz "Enter number : \n"
+szCarriageReturn:  .asciz "\n"
+
+/* UnInitialized data */
+.bss
+sBuffer:    .skip    BUFFERSIZE
+
+/*  code section */
+.text
+.global main
+main:                /* entry of program  */
+    push {fp,lr}    /* saves 2 registers */
+    ldr r0,iAdrszMessDeb
+    bl affichageMess
+    mov r0,#STDIN         @ Linux input console
+    ldr r1,iAdrsBuffer   @ buffer address
+    mov r2,#BUFFERSIZE   @ buffer size
+    mov r7, #READ         @ request to read datas
+    swi 0                  @ call system
+    ldr r1,iAdrsBuffer    @ buffer address
+    mov r2,#0                @ end of string
+    strb r2,[r1,r0]         @ store byte at the end of input string (r0 contains number of characters)
+
+    ldr r0,iAdrsBuffer    @ buffer address
+    bl affichageMess
+    ldr r0,iAdrszCarriageReturn
+    bl affichageMess
+
+    ldr r0,iAdrszMessNum
+    bl affichageMess
+    mov r0,#STDIN         @ Linux input console
+    ldr r1,iAdrsBuffer   @ buffer address
+    mov r2,#BUFFERSIZE   @ buffer size
+    mov r7, #READ         @ request to read datas
+    swi 0                  @ call system
+    ldr r1,iAdrsBuffer    @ buffer address
+    mov r2,#0                @ end of string
+    strb r2,[r1,r0]         @ store byte at the end of input string (r0
+    @
+    ldr r0,iAdrsBuffer    @ buffer address
+    bl conversionAtoD    @ conversion string in number in r0
+
+100:   /* standard end of the program */
+    mov r0, #0                  @ return code
+    pop {fp,lr}                 @restaur 2 registers
+    mov r7, #EXIT              @ request to exit program
+    swi 0                       @ perform the system call
+
+iAdrszMessDeb:  .int szMessDeb
+iAdrszMessNum: .int  szMessNum
+iAdrsBuffer:   .int  sBuffer
+iAdrszCarriageReturn:  .int  szCarriageReturn
+/******************************************************************/
+/*     display text with size calculation                         */
+/******************************************************************/
+/* r0 contains the address of the message */
+affichageMess:
+    push {fp,lr}    			/* save  registres */
+    push {r0,r1,r2,r7}    		/* save others registers */
+    mov r2,#0   				/* counter length */
+1:      	/* loop length calculation */
+    ldrb r1,[r0,r2]  			/* read octet start position + index */
+    cmp r1,#0       			/* if 0 its over */
+    addne r2,r2,#1   			/* else add 1 in the length */
+    bne 1b          			/* and loop */
+                                /* so here r2 contains the length of the message */
+    mov r1,r0        			/* address message in r1 */
+    mov r0,#STDOUT      		/* code to write to the standard output Linux */
+    mov r7, #WRITE             /* code call system "write" */
+    swi #0                      /* call systeme */
+    pop {r0,r1,r2,r7}     		/* restaur others registers */
+    pop {fp,lr}    				/* restaur des  2 registres */
+    bx lr	        			/* return  */
+
+/******************************************************************/
+/*     Convert a string to a number stored in a registry          */
+/******************************************************************/
+/* r0 contains the address of the area terminated by 0 or 0A */
+/* r0 returns a number                           */
+conversionAtoD:
+    push {fp,lr}         @ save 2 registers
+    push {r1-r7}         @ save others registers
+    mov r1,#0
+    mov r2,#10           @ factor
+    mov r3,#0            @ counter
+    mov r4,r0            @ save address string -> r4
+    mov r6,#0            @ positive sign by default
+    mov r0,#0            @ initialization to 0
+1:     /* early space elimination loop */
+    ldrb r5,[r4,r3]     @ loading in r5 of the byte located at the beginning + the position
+    cmp r5,#0            @ end of string -> end routine
+    beq 100f
+    cmp r5,#0x0A        @ end of string -> end routine
+    beq 100f
+    cmp r5,#' '          @ space ?
+    addeq r3,r3,#1      @ yes we loop by moving one byte
+    beq 1b
+    cmp r5,#'-'          @ first character is -
+    moveq r6,#1         @  1 -> r6
+    beq 3f              @ then move on to the next position
+2:   /* beginning of digit processing loop */
+    cmp r5,#'0'          @ character is not a number
+    blt 3f
+    cmp r5,#'9'          @ character is not a number
+    bgt 3f
+    /* character is a number */
+    sub r5,#48
+    ldr r1,iMaxi       @ check the overflow of the register
+    cmp r0,r1
+    bgt 99f            @ overflow error
+    mul r0,r2,r0         @ multiply par factor 10
+    add r0,r5            @ add to  r0
+3:
+    add r3,r3,#1         @ advance to the next position
+    ldrb r5,[r4,r3]     @ load byte
+    cmp r5,#0            @ end of string -> end routine
+    beq 4f
+    cmp r5,#0x0A            @ end of string -> end routine
+    beq 4f
+    b 2b                 @ loop
+4:
+    cmp r6,#1            @ test r6 for sign
+    moveq r1,#-1
+    muleq r0,r1,r0       @ if negatif, multiply par -1
+    b 100f
+99:  /* overflow error */
+    ldr r0,=szMessErrDep
+    bl   affichageMess
+    mov r0,#0      @ return  zero  if error
+100:
+    pop {r1-r7}          @ restaur other registers
+    pop {fp,lr}          @ restaur   2 registers
+    bx lr                 @return procedure
+/* constante program */	
+iMaxi: .int 1073741824	
+szMessErrDep:  .asciz  "Too large: overflow 32 bits.\n"