; In this example an ISR triggers when TA overflows.. Toggle rate is exactly 0.5Hz.. Dang ; Texas Instruments Inc.
Trang 1; MSP430G2xx1 Demo - Timer_A, Toggle P1.0, Overflow ISR, 32kHz ACLK
;
; Description: Toggle P1.0 using software and the Timer_A overflow ISR
; In this example an ISR triggers when TA overflows Inside the ISR P1.0
; is toggled Toggle rate is exactly 0.5Hz
; ACLK = TACLK = LFXT1 = 32768Hz, MCLK = SMCLK = default DCO
; //* An external watch crystal on XIN XOUT is required for ACLK *//
;
; MSP430G2xx1
;
-; /|\|
XIN|-; | | | 32kHz
; |RST
XOUT|-; | |
; | P1.0| >LED
;
; D Dang
; Texas Instruments Inc
; October 2010
; Built with Code Composer Essentials Version: 4.2.0
;******************************************************************************* .cdecls C,LIST, "msp430g2231.h"
.text ; Progam Start
; -RESET mov.w #0280h,SP ; Initialize stackpointer
StopWDT mov.w #WDTPW+WDTHOLD,&WDTCTL ; Stop WDT
SetupP1 bis.b #001h,&P1DIR ; P1.0 output
SetupTA mov.w #TASSEL_1+MC_2+TAIE,&TACTL ; ACLK, contmode interrupt
;
Mainloop bis.w #LPM3+GIE,SR ; Enter LPM3, interrupts enabled nop ; Required only for debugger
;
; -TAX_ISR; Common ISR for CCR1-4 and overflow
add.w &TAIV,PC ; Add Timer_A offset vector
reti ; CCR0 - no source
reti ; CCR1
reti ; CCR2
reti ; CCR3
reti ; CCR4
TA_over xor.b #001h,&P1OUT ; Toggle P1.0
reti ; Return from overflow ISR
;
; -; Interrupt Vectors
.sect ".reset" ; MSP430 RESET Vector
short RESET ;
sect ".int08" ; Timer_AX Vector
short TAX_ISR ;
end