;*****************************
;                           ;*
;  正弦波(三角波）發生器    ;*
;  AT89C2051，12MHZ晶振     ;*
;  2003.09.12               ;*
;                           ;*
;*****************************
;
;正弦波發生器，p3.0口按鍵減小輸出頻率，P3.1口按鍵增加輸出頻率
;P1口輸出正弦波，（P2口輸出余弦波），使用定時器T0，16位定時模式。
;R6、R7用作10毫秒延時寄存器。p3.7輸出方波
;
SINP         DATA       30H  ;正弦波查表指針
;COSP         DATA       31H  ;余弦波查表指針
TH0D         DATA       32H  ;定時器初值存放（高8位）
TL0D         DATA       33H  ;定時器初值存放（低8位）
;
ORG     0000H
LJMP    START
ORG     000BH
LJMP    INTT0
;
ORG     0060H
;
START:  MOV   SP,#70H
        MOV   SINP,#00H
;        MOV   COSP,#40H
        MOV   TMOD,#11H
        MOV   TH0D,#0FFH   ;初值，決定波形頻率
        MOV   TL0D,#00H
        MOV   TH0,TH0D
        MOV   TL0,TL0D
        MOV   DPTR,#LIST
        SETB  ET0
        SETB  EA
        SETB  TR0
MAIN:   JNB   p3.0,INCKEY
        JNB   P3.1,DECKEY
        ORL   PCON,#01H
        LJMP  MAIN
;  按鍵功能，輸出頻率減小
INCKEY:LCALL  DL10MS
       JB     p3.0,MAIN
       MOV    A,TL0D
       CJNE   A,#0FFH,INC1
       LJMP   MAIN
INC1:  INC    TL0D
       LJMP   MAIN
; 按鍵功能，輸出頻率增大
DECKEY:LCALL  DL10MS
       JB     P3.1,MAIN
       MOV    A,TL0D
       CJNE   A,#00H,DEC1
       LJMP   MAIN
DEC1:  DEC    TL0D
       LJMP   MAIN
; 定時器T0中斷程序
INTT0: PUSH   ACC
       CPL    P3.7           ;方波輸出,作輔助功能用
       MOV    TH0,TH0D
       MOV    TL0,TL0D
       MOV    A,SINP
       MOVC   A,@A+DPTR
       MOV    P1,A           ;正弦波從P1口輸出
;      MOV    A,COSP
;      MOVC   A,@A+DPTR      ;
;      MOV    P2,A           ;余弦波從P2口輸出
       INC    SINP
;       INC    COSP
       POP    ACC
       RETI
; 10毫秒延時程序
DL512: MOV    R7,#0FFH
LOOP:  DJNZ   R7,LOOP
       RET
DL10MS:MOV    R6,#14H
LOOP1: LCALL  DL512
       DJNZ   R6,LOOP1
       RET
;  正弦函數表（共256個點，每點1.40625度）
LIST:  DB  80H,83H,85H,88H,8AH,8DH,8FH,92H
       DB  94H,97H,99H,9BH,9EH,0A0H,0A3H,0A5H
       DB  0A7H,0AAH,0ACH,0AEH,0B1H,0B3H,0B5H,0B7H
       DB  0B9H,0BBH,0BDH,0BFH,0C1H,0C3H,0C5H,0C7H
       DB  0C9H,0CBH,0CCH,0CEH,0D0H,0D1H,0D3H,0D4H
       DB  0D6H,0D7H,0D8H,0DAH,0DBH,0DCH,0DDH,0DEH
       DB  0DFH,0E0H,0E1H,0E2H,0E3H,0E3H,0E4H,0E4H
       DB  0E5H,0E5H,0E6H,0E6H,0E7H,0E7H,0E7H,0E7H
       DB  0E7H,0E7H,0E7H,0E7H,0E6H,0E6H,0E5H,0E5H
       DB  0E4H,0E4H,0E3H,0E3H,0E2H,0E1H,0E0H,0DFH
       DB  0DEH,0DDH,0DCH,0DBH,0DAH,0D8H,0D7H,0D6H
       DB  0D4H,0D3H,0D1H,0D0H,0CEH,0CCH,0CBH,0C9H
       DB  0C7H,0C5H,0C3H,0C1H,0BFH,0BDH,0BBH,0B9H
       DB  0B7H,0B5H,0B3H,0B1H,0AEH,0ACH,0AAH,0A7H
       DB  0A5H,0A3H,0A0H,9EH,9BH,99H,97H,94H
       DB  92H,8FH,8DH,8AH,88H,85H,83H,80H
       DB  7DH,7BH,78H,76H,73H,71H,6EH,6CH
       DB  69H,67H,65H,62H,60H,5DH,5BH,59H
       DB  56H,54H,52H,4FH,4DH,4BH,49H,47H
       DB  45H,43H,41H,3FH,3DH,3BH,39H,37H
       DB  35H,34H,32H,30H,2FH,2DH,2CH,2AH
       DB  29H,28H,26H,25H,24H,23H,22H,21H
       DB  20H,1FH,1EH,1DH,1DH,1CH,1CH,1BH
       DB  1BH,1AH,1AH,1AH,19H,19H,19H,19H
       DB  19H,19H,19H,19H,1AH,1AH,1AH,1BH
       DB  1BH,1CH,1CH,1DH,1DH,1EH,1FH,20H
       DB  21H,22H,23H,24H,25H,26H,28H,29H
       DB  2AH,2CH,2DH,2FH,30H,32H,34H,35H
       DB  37H,39H,3BH,3DH,3FH,41H,43H,45H
       DB  47H,49H,4BH,4DH,4FH,52H,54H,56H
       DB  59H,5BH,5DH,60H,62H,65H,67H,69H
       DB  6CH,6EH,71H,73H,76H,78H,7BH,7DH
;  三角波函數表
LIST1: DB  80H,81H,82H,83H,84H,85H,86H,87H
       DB  88H,89H,8AH,8BH,8CH,8DH,8EH,8FH
       DB  90H,91H,92H,93H,94H,95H,96H,97H
       DB  98H,99H,9AH,9BH,9CH,9DH,9EH,9FH
       DB  0A0H,0A1H,0A2H,0A3H,0A4H,0A5H,0A6H,0A7H
       DB  0A8H,0A9H,0AAH,0ABH,0ACH,0ADH,0AEH,0AFH
       DB  0B0H,0B1H,0B2H,0B3H,0B4H,0B5H,0B6H,0B7H
       DB  0B8H,0B9H,0BAH,0BBH,0BCH,0BDH,0BEH,0BFH
       DB  0BFH,0BEH,0BDH,0BCH,0BBH,0BAH,0B9H,0B8H
       DB  0B7H,0B6H,0B5H,0B4H,0B3H,0B2H,0B1H,0B0H
       DB  0AFH,0AEH,0ADH,0ACH,0ABH,0AAH,0A9H,0A8H
       DB  0A7H,0A6H,0A5H,0A4H,0A3H,0A2H,0A1H,0A0H
       DB  9FH,9EH,9DH,9CH,9BH,9AH,99H,98H
       DB  97H,96H,95H,94H,93H,92H,91H,90H
       DB  8FH,8EH,8DH,8CH,8BH,8AH,89H,88H
       DB  87H,86H,85H,84H,83H,82H,81H,80H
       DB  7FH,7EH,7DH,7CH,7BH,7AH,79H,78H
       DB  77H,76H,75H,74H,73H,72H,71H,70H
       DB  6FH,6EH,6DH,6CH,6BH,6AH,69H,68H
       DB  66H,66H,65H,64H,63H,62H,61H,60H
       DB  5FH,5EH,5DH,5CH,5BH,5AH,59H,58H
       DB  55H,55H,55H,54H,53H,52H,51H,50H
       DB  4FH,4EH,4DH,4CH,4BH,4AH,49H,48H
       DB  44H,44H,45H,44H,43H,42H,41H,40H
       DB  40H,41H,42H,43H,44H,45H,46H,47H
       DB  48H,49H,4AH,4BH,4CH,4DH,4EH,4FH
       DB  50H,51H,52H,53H,55H,55H,56H,57H
       DB  58H,59H,5AH,5BH,5CH,5DH,5EH,5FH
       DB  60H,61H,62H,63H,66H,65H,66H,67H
       DB  68H,69H,6AH,6BH,6CH,6DH,6EH,6FH
       DB  70H,71H,72H,73H,77H,75H,76H,77H
       DB  78H,79H,7AH,7BH,7CH,7DH,7EH,7FH
;
       END