;******************************************************************************
;   MSP430x42x0 Demo - Timer_A, Toggle P1.0, CCR0 Cont. Mode ISR, DCO SMCLK
;
;   Description: Toggle P1.0 using software and TA_0 ISR. Toggles every
;   50000 SMCLK cycles. SMCLK provides clock source for TACLK.
;   During the TA_0 ISR P1.0 is toggled and 50000 clock cycles are added to
;   CCR0. TA_0 ISR is triggered every 50000 cycles. CPU is normally off and
;   used only during TA_ISR.
;   ACLK = n/a, MCLK = SMCLK = TACLK = default DCO
;
;                MSP430F4270
;             -----------------
;         /|\|              XIN|-
;          | |                 |
;          --|RST          XOUT|-
;            |                 |
;            |             P1.0|-->LED
;
;  L. Westlund / S. Karthikeyan
;  Texas Instruments Inc.
;  June 2005
;  Built with IAR Embedded Workbench Version: 3.30A
;******************************************************************************
#include  <msp430x42x0.h>
;------------------------------------------------------------------------------
            ORG     08000h                  ; Program Start
;------------------------------------------------------------------------------
RESET       mov.w   #300h,SP                ; Initialize stackpointer
StopWDT     mov.w   #WDTPW+WDTHOLD,&WDTCTL  ; Stop WDT
SetupP5     bis.b   #001h,&P1DIR            ; P1.0 output
SetupC0     mov.w   #CCIE,&CCTL0            ; CCR0 interrupt enabled
            mov.w   #50000,&CCR0            ;
SetupTA     mov.w   #TASSEL_2+MC_2,&TACTL   ; SMCLK, continuous mode
                                            ;						
Mainloop    bis.w   #CPUOFF+GIE,SR          ; CPU off, interrupts enabled
            nop                             ; Required for debugger
                                            ;
;------------------------------------------------------------------------------
TA0_ISR;    Toggle P5.1
;------------------------------------------------------------------------------
            xor.b   #001h,&P1OUT            ; Toggle P1.0
            add.w   #50000,&CCR0            ; Add offset to CCR0
            reti                            ;		
                                            ;
;-----------------------------------------------------------------------------
;           Interrupt Vectors
;-----------------------------------------------------------------------------
            ORG     0FFFEh                  ; RESET Vector
            DW      RESET                   ;
            ORG     0FFECh                  ; Timer_A0 Vector
            DW      TA0_ISR                 ;
            END