adctimer.lst

aduc842原程序代码 ad公司芯片应用笔记

ADCTIMER                                                                                                      PAGE 1

                       1    ;********************************************************************
                       2    ;
                       3    ; Author        : ADI - Apps            www.analog.com/MicroConverter
                       4    ;
                       5    ; Date          : October 2003
                       6    ;
                       7    ; File          : ADCtimer.asm
                       8    ;
                       9    ; Hardware      : ADuC842/ADuC843
                      10    ;
                      11    ; Description   : Performs ADC conversions at 116KSPS in Timer2 mode.
                      12    ;                 Outputs ADC results to RAM.  Continuously
                      13    ;                 flashes LED (independently of ADC routine) at
                      14    ;                 approximately 3Hz.
                      15    ;                 All rate calculations assume an 2.097152MHz Mclk.
                      16    ;               
                      17    ;********************************************************************
                      18    
                      19    $MOD842                         ; Use 8052&ADuC842 predefined symbols
                      20    
  00B4                21    LED     EQU     P3.4            ; P3.4 drives red LED on eval board
  0000                22    CHAN    EQU     0               ; convert this ADC input channel..
                      23                                    ; ..chan values can be 0 thru 6
                      24    
----                  25    DSEG 
0030                  26    ORG 0030H
  0028                27    LENGTH EQU 40
0030                  28    BUFFER: DS LENGTH                ; set up buffer in RAM
                      29    
                      30    ;____________________________________________________________________
                      31                                                      ; BEGINNING OF CODE
----                  32    CSEG
                      33    
0000                  34    ORG 0000h
                      35    
0000 02004B           36            JMP     MAIN            ; jump to main program
                      37    ;____________________________________________________________________
                      38                                                 ; INTERRUPT VECTOR SPACE
0033                  39    ORG 0033H ; (ADC ISR)
0033 B85803           40            CJNE    R0,#58H,CONT
0036 02003F           41            JMP     EXIT            ; place breakpoint here to view ram in debugger after conver
                                                                               sions
0039 A6DA             42    CONT:   MOV     @R0,ADCDATAH
003B 08               43            INC     R0
003C A6D9             44            MOV     @R0,ADCDATAL            
003E 08               45            INC     R0
003F 32               46    EXIT:   RETI    
                      47            
                      48    
                      49    ;====================================================================
                      50                                                           ; MAIN PROGRAM
004B                  51    ORG 004Bh
                      52    
004B 7830             53    MAIN:   MOV     R0,#BUFFER
                      54    ; PRECONFIGURE...
004D 75EF9E           55            MOV     ADCCON1,#09Eh   ; power up ADC & enable Timer2 mode
0050 75D800           56            MOV     ADCCON2,#CHAN   ; select channel to convert
0053 75CAF6           57            MOV     RCAP2L,#0F6h    ; sample period = 2 * T2 reload prd
ADCTIMER                                                                                                      PAGE 2

0056 75CBFF           58            MOV     RCAP2H,#0FFh    ;   = 2*(10000h-FFF6h)*0.476us
0059 75CCF6           59            MOV     TL2,#0F6h       ;   = 2*9*0.476us
005C 75CDFF           60            MOV     TH2,#0FFh       ;   = 8.5us
                      61    
                      62    ; LAUNCH Timer2 DRIVEN CONVERSIONS...
005F D2AF             63            SETB    EA              ; enable interrupts
0061 D2AE             64            SETB    EADC            ; enable ADC interrupt
0063 D2CA             65            SETB    TR2             ; run Timer2
                      66    
                      67    ; CONTINUE WITH OTHER CODE...
0065 B2B4             68    AGAIN:  CPL     LED             ; blink (complement) the LED
0067 740A             69            MOV     A,#010          ; Delay length
0069 12006E           70            CALL    DELAY           ; delay 100ms
006C 80F7             71            JMP     AGAIN           ; repeat
                      72    
                      73    ; the micro is free to continue with other tasks (flashing the LED in
                      74    ; this case) while the ADC operation is being controlled by Timer2
                      75    ; and the ADC interrupt service routine.
                      76    
                      77    ;____________________________________________________________________
                      78                                                             ; SUBROUTINE
006E                  79    DELAY:                                  ; Delays by 10ms * A
                      80                                            ; 10mSec based on 2.09MHZ 
                      81                                            ; Core Clock 
                      82                                            ; i.e. default ADuC842 Clock
                      83    
006E F9               84                    MOV     R1,A            ; Acc holds delay variable (1 clock)
006F 7A1B             85     DLY0:          MOV     R2,#01Bh        ; Set up delay loop0 (2 clocks)
0071 7BFF             86     DLY1:          MOV     R3,#0FFh        ; Set up delay loop1 (2 clocks)
0073 DBFE             87                    DJNZ    R3,$            ; Dec R3 & Jump here until R3 is 0 (3 clocks)
0075 DAFA             88                    DJNZ    R2,DLY1         ; Dec R2 & Jump DLY1 until R2 is 0 (3 clocks)
0077 D9F6             89                    DJNZ    R1,DLY0         ; Dec R1 & Jump DLY0 until R1 is 0 (3 clocks)
0079 22               90                    RET                     ; Return from subroutine
                      91    
                      92    ;____________________________________________________________________
                      93    
                      94    END

VERSION 1.2h ASSEMBLY COMPLETE, 0 ERRORS FOUND
ADCTIMER                                                                                                      PAGE 3

ADCCON1. . . . . . . . . . . . .  D ADDR  00EFH  PREDEFINED  
ADCCON2. . . . . . . . . . . . .  D ADDR  00D8H  PREDEFINED  
ADCDATAH . . . . . . . . . . . .  D ADDR  00DAH  PREDEFINED  
ADCDATAL . . . . . . . . . . . .  D ADDR  00D9H  PREDEFINED  
AGAIN. . . . . . . . . . . . . .  C ADDR  0065H  
BUFFER . . . . . . . . . . . . .  D ADDR  0030H  
CHAN . . . . . . . . . . . . . .    NUMB  0000H  
CONT . . . . . . . . . . . . . .  C ADDR  0039H  
DELAY. . . . . . . . . . . . . .  C ADDR  006EH  
DLY0 . . . . . . . . . . . . . .  C ADDR  006FH  
DLY1 . . . . . . . . . . . . . .  C ADDR  0071H  
EA . . . . . . . . . . . . . . .  B ADDR  00AFH  PREDEFINED  
EADC . . . . . . . . . . . . . .  B ADDR  00AEH  PREDEFINED  
EXIT . . . . . . . . . . . . . .  C ADDR  003FH  
LED. . . . . . . . . . . . . . .    NUMB  00B4H  
LENGTH . . . . . . . . . . . . .    NUMB  0028H  
MAIN . . . . . . . . . . . . . .  C ADDR  004BH  
P3 . . . . . . . . . . . . . . .  D ADDR  00B0H  PREDEFINED  
RCAP2H . . . . . . . . . . . . .  D ADDR  00CBH  PREDEFINED  
RCAP2L . . . . . . . . . . . . .  D ADDR  00CAH  PREDEFINED  
TH2. . . . . . . . . . . . . . .  D ADDR  00CDH  PREDEFINED  
TL2. . . . . . . . . . . . . . .  D ADDR  00CCH  PREDEFINED  
TR2. . . . . . . . . . . . . . .  B ADDR  00CAH  PREDEFINED