Converter ARM

converter.s

;The semicolon is used to lead an inline documentation
;When you write your program, you could have your info at the top document block
;For Example:  Your Name, Student Number, what the program is for, and what it does etc.
;
;       See if you can figure out what this program does
;

;;; Directives
          PRESERVE8
          THUMB       
 
; Vector Table Mapped to Address 0 at Reset
; Linker requires __Vectors to be exported
 
          AREA    RESET, DATA, READONLY
          EXPORT  __Vectors
 
__Vectors 
	  DCD  0x20001000     ; stack pointer value when stack is empty
          DCD  Reset_Handler  ; reset vector
  
          ALIGN
		  
;Your Data section
;AREA DATA

FSTART 	DCD 70
CSTART  DCD 22
; The DCD directive allocates one or more words of memory,
; aligned on four-byte boundaries,
; and defines the initial runtime contents of the memory.
;
; For example,   data1   DCD     1,5,20
; Defines 3 words containing decimal values 1, 5, and 20

 	 AREA    MYRAM, DATA, READWRITE
SUM 	DCD 0


 
; The program
; Linker requires Reset_Handler
 
          AREA    MYCODE, CODE, READONLY
 
   	  ENTRY
   	  EXPORT Reset_Handler
 
 
Reset_Handler
;;;;;;;;;;User Code Start from the next line;;;;;;;;;;;;

	LDR R0, CSTART ;load celcuis start     ;R0
   	LDR R2, FSTART ;load farenheit start   ;R2
    
	
	MOV R11, #9 ;load 9 to mul orig val by ;R11
	MOV R12, #5 ;load 5 to mul by          ;R12
	
	MUL R1, R0, R11 ;mul R0 * 9             ;R1
	SDIV R1, R1, R12 ;div prod by 5
	
	ADD R1, R1, #32 ;converted Cel is in R1
	
	SUB R5, R2, #32; ;subtract from Faren
	MUL R4, R5, R12 ;mul diff by 5
	SDIV R3, R4, R11 ;div prod by 9
	

	ALIGN
STOP
        B  STOP


	END