;-------------------------------------------------------------------------------
; MSP430 Assembler Code Template for use with TI Code Composer Studio
;
;
;-------------------------------------------------------------------------------
            .cdecls C,LIST,"msp430.h"       ; Include device header file
            
;-------------------------------------------------------------------------------
            .def    RESET                   ; Export program entry-point to
                                            ; make it known to linker.
;-------------------------------------------------------------------------------
			.data
myStr:		.cstring  "!#$%&()*+,-./:;<=>?@[\\]^_`{|}~" 		; Define cstring variable
symb_count: .int      0                     ; counter variable
            .text                           ; Assemble into program memory.
            .retain                         ; Override ELF conditional linking
                                            ; and retain current section.
            .retainrefs                     ; And retain any sections that have
                                            ; references to current section.

;-------------------------------------------------------------------------------
RESET       mov.w   #__STACK_END,SP         ; Initialize stackpointer
StopWDT     mov.w   #WDTPW|WDTHOLD,&WDTCTL  ; Stop watchdog timer


;-------------------------------------------------------------------------------
; Main loop here
;-------------------------------------------------------------------------------
main:      mov.w  #myStr, R4                ; Move the starting address of myStr into register 4
		   clr.b  R5					  	; Register 5 will serve as a counter
gnext:     mov.b  @R4+, R6                  ; get a new character
		   cmp.b  #0, R6                    ; check for null character
		   jeq    lend						; if null, go to end
		   cmp.b  #97, R6	    			; check if 'a'
		   jeq    gnext						; if equal, get next character
		   jge    range2					; if greater or equal, jump to range2
		   jl     capitals					; if less than, jump to numbers label

range2:    cmp.b #123, R6					; is it '{' char
		   jge	 incr						; if it is, jump to incr
		   jl    gnext						; if less than, get next character

capitals:  cmp.b #91, R6					; is it '['
		   jge   incr						; if it is or greater, jump to incr
		   cmp.b #65, R6					; is it 'A'
		   jge   gnext						; if equal or greater, get next character
		   cmp.b #58, R6					; is it ';'
		   jge   incr						; if greater or equal, jump to incr
		   cmp.b #48, R6					; is it '0'
		   jge   gnext						; if equal or greater, get next character
incr:      inc.w R5							; increment counter
		   jmp   gnext						; get next character

lend:      mov.w   R5,&P1OUT                ; Write result in P1OUT (not visible on port pins)
           bis.w   #LPM4, SR               	; LPM4
           nop                             	; Required only for debugger

;-------------------------------------------------------------------------------
; Stack Pointer definition
;-------------------------------------------------------------------------------
            .global __STACK_END
            .sect   .stack
            
;-------------------------------------------------------------------------------
; Interrupt Vectors
;-------------------------------------------------------------------------------
            .sect   ".reset"                ; MSP430 RESET Vector
            .short  RESET