程序清單：
        DAADR EQU 7FFEH
        INO EQU 7FF8H
        IN1 EQU 7FF9H
        IN2 EQU 7FFAH
        ORG 0000H
        AJMP MAIN
        ORG 0030H
MAIN:  MOV SP,#70H                  ;設(shè)置堆棧指針
        LCALL ADC                   ;調(diào)用A/D轉(zhuǎn)換程序
        LCALL DISP                   ;調(diào)用顯示子程序
        MOV A,30H           
        CJNE A,#80H,AA               ;判斷頻率高低，確定發(fā)送點(diǎn)數(shù) 
AA:     JC A1
        CJNE A,#0C0H,BB
BB:     JC A2
        MOV R7,#5
        AJMP WAVE
A1:     MOV R7,#1
        AJMP WAVE
A2:     MOV R7,#3
        AJMP WAVE
;********初始檢測(cè)有無按鍵按下******************
WAVE:   JB P2.0,ZH1           ;按鍵按下為低電平
        LCALL DELAY0
ZH1:    JNB P2.0,ZHJC         ;跳到鋸齒波發(fā)生程序
        JB P2.2,ZH2
        LCALL DELAY0        ;延時(shí)去抖
ZH2:    JNB P2.2,SAN          ;跳到三角波發(fā)生程序
        JB P2.3,ZH3 
        LCALL DELAY0
ZH3:    JNB P2.3,SIN          ;跳到正弦波發(fā)生程序
        JB P2.1,ZH4
        LCALL DELAY0
ZH4:    JNB P2.1,FANJC        ;跳到方波發(fā)生程序
        AJMP  WAVE
;*****************波形產(chǎn)生函數(shù)*****************
ZHJC:   MOV DPTR,#DAADR    ;正向鋸齒波
DA1:    MOV R6,#00H
DA2:    MOV A,R6
        ADD A,R7
        MOVX @DPTR,A        ;將數(shù)據(jù)送到D/A轉(zhuǎn)換模塊
        LCALL DELAY
        LCALL DELAY1
        MOV 33H,P2             ;掃描按鍵，如果有鍵按下則返回
        ORL 33H,#0F0H
        MOV R5,33H
        CJNE R5,#0FFH,DA3        
        CJNE R6,#0FFH,DA2
        AJMP DA1
DA3:    RET
SAN:    MOV DPTR,#DAADR       ;三角波
        MOV R6,#00H
        MOV A,R7
        RL  A
        MOV R7,A
        MOV A,R6
DA5:    ADD A,R7
        MOVX @DPTR,A
        LCALL DELAY
        LCALL DELAY1
        MOV 33H,P2
        ORL 33H,#0F0H
        MOV R5,33H
        CJNE R5,#0FFH,DA8
        CJNE A,#0FFH,DA5
DA7:    SUBB A,R7
        MOVX @DPTR,A
        LCALL DELAY
        LCALL DELAY1
        MOV 33H,P2
        ORL 33H,#0F0H
        MOV R5,33H
        CJNE R5,#0FFH,DA8
        CJNE A,#00H,DA7
DA8:    RET
SINS:   MOV  R6,#00H
        MOV A,R6             ;單路正弦波
SIN:    ADD A,R7
        MOV DPTR,#TABH     ;取正弦值表首地址
        MOVC A,@A+DPTR
        MOV DPTR,#DAADR
        MOVX @DPTR,A
        LCALL DELAY
        LCALL DELAY1
        MOV 33H,P2
        ORL 33H,#0F0H
        MOV R5,33H
        CJNE R5,#0FFH,SIN2
        AJMP SIN
SIN2:   RET
FANJC:  MOV DPTR,#DAADR     ;方波
        MOV R6,#00H
        MOV A,R7
        RL  A
        MOV R7,A
        MOV A,R6
FAN5:   ADD A,R7
        MOV R6,A
        MOV A,#0FFH
        MOVX @DPTR,A
        LCALL DELAY
        LCALL DELAY1
        MOV 33H,P2
        ORL 33H,#0F0H
        MOV R5,33H
        CJNE R5,#0FFH,FAN8
        CJNE R6,#0FFH,FAN5
FAN7:   MOV A,R6
        SUBB A,R7
        MOV R6,A
        MOV A,#00H
        MOVX @DPTR,A
        LCALL DELAY
        LCALL DELAY1
        MOV 33H,P2
        ORL 33H,#0F0H
        MOV R5,33H
        CJNE R5,#0FFH,FAN8
        CJNE R6,#00H,FAN7
FAN8:   RET
;***************A/D轉(zhuǎn)換****************
ADC:   MOV DPTR,#7FF8H     ;P2.7=0, 且指向IN0
        MOV R1,#30H          ;置數(shù)碼區(qū)首地址
        MOV R2,#02
READ:  MOVX @DPTR,A
HERE:  JNB P2.5,HERE        ;等待轉(zhuǎn)換結(jié)束
        MOVX A,@DPTR       ;讀取轉(zhuǎn)換后數(shù)據(jù)
        MOVX @R1,A
        INC R1
        INC DPTR
        DJNZ R2,READ
        SETB RS0             ;選擇寄存器組1
        RR A                 ;經(jīng)過計(jì)算得到延時(shí)程序初值
        MOV R3,#9CH
        MOV R4,#40H
        CLR C
        XCH A,R4
        SUBB A,R4
        MOV R4,A
        MOV A,30H
        RR A
        XCH A,R3
        SUBB A,B
        MOV R3,A
        MOV R1,A
        MOV A,R4
        MOV B,#02H
        DIV AB
        MOV R3,A
        CLR RS0
        RET
;**********碼制變換和顯示程序***************
DISP:   SETB RS1          ;選擇寄存器組2
       ;兩個(gè)通道待轉(zhuǎn)換的數(shù)據(jù)分別以十六進(jìn)制形式放置在30H、31H
       ;40H和41H存放通道0轉(zhuǎn)換的后BCD碼
       ;42H和43H存放通道1轉(zhuǎn)換后的BCD碼
       ;將通道0的數(shù)據(jù)轉(zhuǎn)換為需要顯示的頻率數(shù)
        MOV  R0,#30H    ;指向通道0的數(shù)據(jù)
        MOV A,@R0
        MOV B,#07H
        DIV AB
        MOV B,#10
        DIV AB
        MOV 40H,A
        MOV 41H,B
       ;將通道1的數(shù)據(jù)轉(zhuǎn)換為需要顯示的頻率數(shù)
        MOV  R0,#31H      ;指向通道0的數(shù)據(jù)
        MOV A,@R0
        MOV B,#07H
        DIV AB
        MOV B,#10
        DIV AB
        MOV 42H,A
        MOV 43H,B
DIR:    SETB RS1            ;選擇寄存器組2
        MOV R2,#04H        ;顯示6個(gè)數(shù)碼管
        MOV  R0,#40H       ;顯示緩沖區(qū)首地址送R0
DL0:    MOV A,@R0         ;取要顯示的數(shù)作查表偏移量
        MOV DPTR,#TAB     ;指向段碼表首
        MOVC A,@A+DPTR   ;查表得段碼
        MOV SBUF,A         ;發(fā)送顯示
DL1:    JNB TI,DL1           ;等待發(fā)送完一幀
        CLR TI               ;清中斷標(biāo)志，準(zhǔn)備繼續(xù)發(fā)送
        INC R0               ;更新顯示單元
        DJNZ R2,DL0         ;重復(fù)顯示所有數(shù)碼管
        CLR RS1             ;恢復(fù)第0組工作寄存器
        RET
;************波形延時(shí)子程序************
;延時(shí)單位256us
DELAY:SETB RS0
       MOV R2,#128
       DJNZ R2,$
       DJNZ R1,DELAY
       CLR RS0
       RET
;************波形延時(shí)程序2************
;延時(shí)單位2us
DELAY1:SETB RS0
        DJNZ R3,DELAY1
        CLR RS0
        RET
;***************按鍵延時(shí)**************
DELAY0:SETB RS0
        SETB RS1
        MOV R2,#20
LOOP2: MOV R3,#250
        DJNZ R3,$
        DJNZ R2,LOOP2
        CLR RS0
        CLR RS1
        RET
TABH:DB 80H,83H,86H,89H,08DH,90H,93H,96H            ;正弦函數(shù)值
      DB 99H,09CH,09FH,0A2H,0A5H,0A8H,0ABH,0AEH
      DB 0B1H,0B4H,0B7H,0BAH,0BCH,0BFH,0C2H,0C5H
      DB 0C7H,0CAH,0CCH,0CFH,0D1H,0D4H,0D6H,0D8H
      DB 0DAH,0DDH,0DFH,0E1H,0E3H,0E5H,0E7H,0E9H
      DB 0EAH,0ECH,0EEH,0EFH,0F1H,0F2H,0F4H,0F5H
      DB 0F6H,0F7H,0F8H,0F9H,0FAH,0FBH,0FCH,0FDH
      DB 0FDH,0FEH,0FFH,0FFH,0FFH,0FFH,0FEH,0FDH
      DB 0FDH,0FCH,0FBH,0FAH,0F9H,0F8H,0F7H,0F6H
      DB 0F5H,0F4H,0F2H,0F1H,0EFH,0EEH,0ECH,0EAH
DB 0E9H,0E7H,0E5H,0E3H,0E1H,0DFH,0DDH,0DAH
      DB 0D8H,0D6H,0D4H,0D1H,0CFH,0CCH,0CAH,0C7H
      DB 0C5H,0C2H,0BFH,0BCH,0BAH,0B7H,0B4H,0B1H
      DB 0AEH,0ABH,0A8H,0A5H,0A2H,09FH,09CH,99H
      DB 96H,93H,90H,08DH,89H,86H,83H,80H
      DB 80H,07CH,79H,76H,72H,06FH,06CH,69H
      
DB 66H,63H,60H,05DH,05AH,57H,55H,51H
      DB 04EH,04CH,48H,45H,43H,40H,03DH,03AH
      DB 38H,35H,33H,30H,02EH,02BH,29H,27H
      DB 25H,22H,20H,01EH,01CH,01AH,18H,16H
      DB 15H,13H,11H,10H,0EH,0DH,0BH,0AH
      DB 09H,08H,07H,06H,05H,04H,03H,02H
      DB 02H,01H,00H,00H,00H,00H,00H,00H
      DB 00H,00H,00H,00H,00H,00H,02H,01H
DB 02H,03H,04H,05H,06H,07H,08H,09H
      DB 0AH,0BH,0DH,0EH,10H,11H,13H,15H
      DB 16H,18H,01AH,01CH,01EH,20H,22H,25H
      DB 27H,29H,02BH,02EH,30H,33H,35H,38H
      DB 03AH,03DH,40H,43H,45H,48H,04CH,04EH
      DB 51H,55H,57H,05AH,05DH,60H,63H,66H
      DB 69H,06CH,06FH,72H,76H,79H,07CH,80H

TAB: DB 03FH,06H,05BH,04FH,66H,06DH,07DH,07H         ;七段碼表
     DB 07FH,06FH,77H,07CH,39H,05EH,79H,71H
     END