;*******************************************************************************
;   MSP430F20xx Demo - Timer_A, Toggle P1.0, CCR0 Up Mode ISR, 32kHz ACLK
;
;   Description: Toggle P1.0 using software and the TA_0 ISR. Timer_A is
;   configured for up mode, thus the timer overflows when TAR counts
;   to CCR0. In this example CCR0 is loaded with 1000-1.
;   ACLK = TACLK = LFXT1 = 32768Hz, MCLK = SMCLK = default DCO
;   //* An external watch crystal on XIN XOUT is required for ACLK *//	
;
;                MSP430F20xx
;             -----------------
;         /|\|              XIN|-
;          | |                 | 32kHz
;          --|RST          XOUT|-
;            |                 |
;            |             P1.0|-->LED
;
;   M. Buccini / L. Westlund
;   Texas Instruments Inc.
;   September 2005
;   Built with IAR Embedded Workbench Version: 3.40A
;*******************************************************************************
#include  "msp430x20x3.h"
;-------------------------------------------------------------------------------
            ORG     0F800h                  ; Program Reset
;-------------------------------------------------------------------------------
RESET       mov.w   #0280h,SP               ; Initialize stackpointer
StopWDT     mov.w   #WDTPW+WDTHOLD,&WDTCTL  ; Stop WDT
SetupP1     bis.b   #001h,&P1DIR            ; P1.0 output
SetupC0     mov.w   #CCIE,&CCTL0            ; CCR0 interrupt enabled
            mov.w   #1000-1,&CCR0           ; CCR0 counts to 1000
SetupTA     mov.w   #TASSEL_1+MC_1,&TACTL   ; ACLK, upmode
                                            ;													
Mainloop    bis.w   #LPM3+GIE,SR            ; Enter LPM3, interrupts enabled
            nop                             ; Required for debugger
                                            ;
;-------------------------------------------------------------------------------
TA0_ISR;    Toggle P1.0
;-------------------------------------------------------------------------------
            xor.b   #001h,&P1OUT            ; Toggle P1.0
            reti                            ;		
                                            ;
;-------------------------------------------------------------------------------
;           Interrupt Vectors
;-------------------------------------------------------------------------------
            ORG     0FFFEh                  ; MSP430 RESET Vector
            DW      RESET                   ;
            ORG     0FFF2h                  ; Timer_A0 Vector
            DW      TA0_ISR                 ;
            END