msp430x24x_adc12_07.s43

步进电机驱动程序msp430f247单片机

;*******************************************************************************
;   MSP430x24x Demo - ADC12, Repeated Single Channel Conversions
;
;   This example shows how to perform repeated conversions on a single channel
;   using "repeat-single-channel" mode.  AVcc is used for the reference and
;   repeated conversions are performed on Channel A0. Each conversion result
;   is stored in ADC12MEM0 and is moved to a RAM location.  The conversion
;   results are moved to RAM addresses 0x1100 - 0x110E.  Test by applying a
;   voltage to channel A0, then running. To view the conversion results, open a
;   memory window in debugger and view the contents of addresses 0x1100 -
;   0x110E after stopping program execution. Remember the conversion results
;   are 12-bits so you must set the memory window to 16-bit mode.
;
;                MSP430x24x
;              ---------------
;             |            XIN|-
;      Vin -->|P6.0/A0        | 32kHz
;             |           XOUT|-
;
;   B. Nisarga
;   Texas Instruments Inc.
;   September 2007
;   Built with IAR Embedded Workbench Version: 3.42A
;*******************************************************************************
#include "msp430x24x.h"

Results     EQU     0200h                  ; Begining of Results table

;-------------------------------------------------------------------------------
            RSEG    CSTACK                  ; Define stack segment
;-------------------------------------------------------------------------------
            RSEG    CODE                    ; Assemble to Flash memory
;-------------------------------------------------------------------------------
RESET       mov.w   #SFE(CSTACK),SP         ; Initialize stackpointer
StopWDT     mov.w   #WDTPW+WDTHOLD,&WDTCTL  ; Stop watchdog
            bis.b   #01h,&P6SEL             ; Enable A/D channel A0
                                            ;
SetupADC12  mov.w   #SHT0_8+MSC+ADC12ON,&ADC12CTL0
                                            ; Turn on ADC12, use int. osc.
                                            ; Extend sampling period to avoid
                                            ; overflow
                                            ; Set MSC so conversions triggered
                                            ; automatically
            mov.w   #SHP+CONSEQ_2,&ADC12CTL1
                                            ; Use sampling timer, set mode
            mov.w   #01h,&ADC12IE           ; Enable ADC12IFG.0 for ADC12MEM0
            clr.w   R5                      ; Clear results table pointer
                                            ;
Mainloop    bis.w   #ENC,&ADC12CTL0         ; Enable conversions
            bis.w   #ADC12SC,&ADC12CTL0     ; Start conversions
            bis.w   #CPUOFF+GIE,SR          ; Hold in LPM0, Enable interrupts
            nop                             ; Need only for debug
                                            ;
;-------------------------------------------------------------------------------
ADC12_ISR   ; Interrupt Service Routine for ADC12
;-------------------------------------------------------------------------------
            mov.w   &ADC12MEM0,Results(R5)  ; Move result, IFG is reset
            incd.w  R5                      ; Increment results table pointer
            and.w   #0Eh,R5                 ; Modulo pointer
            reti                            ;
;-------------------------------------------------------------------------------
            COMMON  INTVEC                  ; Interrupt Vectors
;-------------------------------------------------------------------------------
            ORG     ADC12_VECTOR            ; ADC12 Vector
            DW      ADC12_ISR
            ORG     RESET_VECTOR            ; POR, ext. Reset
            DW      RESET
            END