fet440_adc12_03.s43

msp430f440的头程序

#include          "msp430x44x.h" // Standard Equations
;******************************************************************************
;   MSP-FET430P440 Demo - ADC12, Extend Sampling Period With SHT bits
;
;   Description: This program shows how to extend the sampling time with the
;                internal sampling timer.
;
;   This example shows how to extend the sampling time using the sampling  
;   timer. In this example, the ADC12OSC is used to provide the sampling period 
;   and the SHT0 bits are set to extend the sampling period to 4xADC12CLKx256.  
;   A single conversion is performed on channel A0. The A/D conversion results 
;   are stored in ADC12MEM0 and are moved to R5 upon completion of the 
;   conversion. Test by setting and running to a break point at "jmp Mainloop."  
;   To view the conversion results, open a register window in C-Spy and view 
;   the contents of R5.
;
;
;                MSP430F449
;              ---------------
;             |               |
;             |      A0 (P6.0)|<---- Vin
;             |               |
;
;
;       M.Mitchell
;       Texas Instruments, Inc
;       January, 2002
;******************************************************************************
;------------------------------------------------------------------------------ 
main        ORG     01100h                  ; Program Start
;------------------------------------------------------------------------------ 
RESET       mov     #0A00h,SP               ; Initialize stackpointer
StopWDT     mov     #WDTPW+WDTHOLD,&WDTCTL  ; Stop watchdog
                                            ;
SetupADC12  mov     #ADC12ON+SHT0_15,&ADC12CTL0 ; Turn on ADC12, set SHT0
                                                ; for longer sampling
            mov     #SHP,&ADC12CTL1         ; Use sampling timer
            bis     #BIT0,&ADC12IE          ; Enable ADC12IFG.0 for ADC12MEM0
            bis     #ENC,&ADC12CTL0         ; Enable conversions    
            eint                            ; Enable interrupts
                                            ;
Mainloop    bis     #ADC12SC,&ADC12CTL0     ; Start conversions
            bis     #LPM0,SR                ; Wait for conversion completion
            nop                             ; Only required for CSPY
            jmp     Mainloop                ; SET BREAKPOINT HERE
                                            ;
;------------------------------------------------------------------------------ 
ADC12ISR    ; Interrupt Service Routine for ADC12
;------------------------------------------------------------------------------
            mov     &ADC12MEM0,R5           ; Move result, IFG is reset
            bic     #CPUOFF,0(SP)           ; Return active
            reti                            ;
                                            ;
;------------------------------------------------------------------------------ 
;           Interrupt Vectors         
;------------------------------------------------------------------------------
            ORG     0FFFEh                  ; MSP430 RESET Vector
            DW      RESET                   ;
            ORG     0FFEEh                  ; ADC12 Interrupt Vector
            DW      ADC12ISR                ;
            END