;-------------------------------------------------------------------------------
; 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.
;-------------------------------------------------------------------------------
            .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
;-------------------------------------------------------------------------------
Setup:
            bis.b   #004h, &P2DIR           ; Set P2.2 to output
                                            ; direction (0000_0100)
            bic.b   #004h, &P2OUT           ; Set P2OUT to 0x0000_0100 (ensure
                                            ; LED1 is off)
            bis.b   #002h, &P2DIR           ; Set P2.1 to output
                                            ; direction (0000_0010)
            bic.b   #002h, &P2OUT           ; Set P2OUT to 0x0000_0010 (ensure
                                            ; LED1 is off)

            bis.w   #GIE, SR                ; Enable Global Interrupts
            bis.b   #001h, &P1IE            ; Enable Port 1 interrupt from bit 0
            bis.b   #001h, &P1IES           ; Set interrupt to call from hi to low
            bic.b   #001h, &P1IFG           ; Clear interrupt flag
			;mov.w   #0, R8					; Counter for inner loop
			bic.b   #0x04,&P2OUT            ; Set P2OUT to 0x0000_0100 (LEDS off)
InfLoop:    mov.w   #0xFFFF, R5             ; Software delay (65,535*16cc/2^20 ~ 1s)
			mov.w   #0, R8					; Counter for inner loop
Iter:
SWDelay1:   nop                             ; 1cc (total delay is 16 cc)
            nop
            nop
            nop
            nop
            nop
            nop
            nop
            nop
            nop
            dec.w  R5                       ; 1cc
            jnz    SWDelay1                 ; 2cc
            inc.b  R8						; 3cc
            cmp    #2, R8					; 4cc
            jnz	   Iter						; jump to Iter
            xor.b  #0x02, P2OUT        		; toggle LED 2
            jmp    InfLoop                  ; goto InfLoop

SW1_ISR:  	bic.b   #001h, &P1IFG           ; Clear interrupt flag
ChkSw1:     bit.b   #01h, &P1IN             ; Check if SW1 is pressed
                                            ; (0000_0001 on P1IN)
            jnz     LExit                   ; If not zero, SW is not pressed
                                            ; loop and check again
Debounce:   mov.w   #2000, R15              ; Set to (2000 * 10 cc )
SWD20ms:    dec.w   R15                     ; Decrement R15
            nop
            nop
            nop
            nop
            nop
            nop
            nop
            jnz     SWD20ms                 ; Delay over?
            bit.b   #00000001b,&P1IN        ; Verify SW1 is still pressed
            jnz     LExit                   ; If not, wait for SW1 press
LEDon:      xor.b   #0x04,P2OUT           	; Turn on LED1
LExit:      reti                            ; Return from interrupt
;-------------------------------------------------------------------------------
; Stack Pointer definition
;-------------------------------------------------------------------------------
            .global __STACK_END
            .sect   .stack
;-------------------------------------------------------------------------------
; Interrupt Vectors
;-------------------------------------------------------------------------------
            .sect   ".reset"                ; MSP430 RESET Vector
            .short  RESET
            .sect   ".int20"				;
            .short  SW1_ISR					; set SW1 Interupt service routine
            .end