Program will ; cycle through the on-chip comparator_A reference voltages with output on ; P1.1.. Normal mode is LPM0 with TA0 triggering interrupt for next mode.. Westlund ; Texas Instru
Trang 1; MSP430F20x1 Demo - Comp_A, Output Reference Voltages on P1.1
;
; Description: Output comparator_A reference levels on P1.1 Program will
; cycle through the on-chip comparator_A reference voltages with output on
; P1.1 Normal mode is LPM0 with TA0 triggering interrupt for next mode
; ACLK = n/a, MCLK = SMCLK = default DCO
;
;
-; /|\|
XIN|-; | | |
; |RST
XOUT|-; | |
; | CA1/P1.1| >Vref
; | |
;
; M Buccini / L Westlund
; Texas Instruments Inc
; November 2005
; Built with IAR Embedded Workbench Version: 3.40A
;*******************************************************************************
#include "msp430x20x1.h"
ORG 0F800h ; Program Reset
; -RESET mov.w #0280h,SP ; Initialize stackpointer
StopWDT mov.w #WDTPW+WDTHOLD,&WDTCTL ; Stop WDT
mov.b #P2CA4,&CACTL2 ; CA1
SetupC0 mov.w #CCIE,&CCTL0 ; CCR0 interrupt enabled
SetupTA mov.w #TASSEL_2+ID_3+MC_2,&TACTL ; SMCLK/8, contmode
eint ; General enable interrupts
;
Mainloop clr.b &CACTL1 ; No reference voltage
bis.w #CPUOFF,SR ; CPU off
Ref1 mov.b #CAREF0+CAON,&CACTL1 ; 0.25*Vcc, Comp on
bis.w #CPUOFF,SR ; CPU off
Ref2 mov.b #CAREF1+CAON,&CACTL1 ; 0.5*Vcc, Comp on
bis.w #CPUOFF,SR ; CPU off
Ref3 mov.b #CAREF1+CAREF0+CAON,&CACTL1 ; 0.55V on P2.3, Comp on bis.w #CPUOFF,SR ; CPU off
jmp Mainloop ;
; -TA0_ISR; Exit LPM0
bic.w #CPUOFF,0(SP) ; Exit LPM0 on RETI
reti ;
;
; -; Interrupt Vectors
ORG 0FFFEh ; MSP430 RESET Vector
DW RESET ;
ORG 0FFF2h ; Timer_A0 Vector
DW TA0_ISR ;
END