【文章內(nèi)容簡介】 表示386EX 內(nèi)部1＃定時器的輸出端，定時器輸出的方波周期＝定時器時常，“IRQ7”表示386EX 內(nèi)部主片8259 的7 號中斷，用作采樣中斷。電路中用RC 電路將S 端方波微分，再和正弦波單元產(chǎn)生的正弦波疊加。注意R 點波形不要超過177。5V，以免數(shù)字化溢出。計算機對有干擾的正弦信號R 通過模數(shù)轉(zhuǎn)換器采樣輸入，然后進行數(shù)字濾波處理，去除干擾，最后送至數(shù)模轉(zhuǎn)換器變成模擬量C 輸出。：：：PUBLIC TKPUBLIC CCPUBLIC aSTACK1 SEGMENT STACK DW 256 DUP(?)STACK1 ENDSDATA SEGMENTTK DB 01HCC DB 10H NCC DW 0000H a DB 90H Ba DW 0000H aYk DW 0000H Xk DW 0000HDATA ENDSCODE SEGMENT ASSUME CS:CODE, DS:DATASTART: MOV AX,DATA MOV DS,AX PUSH DS MOV AX,0000H MOV DS,AX MOV AX,OFFSET IRQ7 。填寫8259的7號中斷矢量入口地址的偏移量 MOV SI,003CH 。填寫8259中斷7的中段矢量 MOV [SI],AX 。填偏移量矢量 MOV AX,CS 。填寫8259中斷矢量入口地址的段地址 MOV SI,003EH 。填寫7號中斷段地址矢量 MOV [SI],AX POP DS CLI 。關(guān)系統(tǒng)總中斷 CALL SYSINTI 。系統(tǒng)初始化 MOV DX,0F043H 。初始化定時器1 定時5ms MOV AL,076H OUT DX,AL MOV DX,0F041H MOV AL,88H OUT DX,AL MOV DX,0F041H MOV AL,13H OUT DX,AL IN AL,21H AND AL,7FH OUT 21H,AL MOV SI,OFFSET CC 。系數(shù)轉(zhuǎn)換成二進制小數(shù) MOV CL,02H CALL DATACHANGE MOV DX,302H MOV AL,80H 。D/A輸出零 OUT DX,AL MOV BL,01H AGAIN: STI HLT JMP AGAINDATACHANGE: 。系數(shù)轉(zhuǎn)換子程序 AND AL,AL MOV DX,0000H MOV BL,10H MOV AL,[SI]GOON: ADD AL,AL DAA RCL DX,0001H DEC BL JNZ GOON INC SI MOV [SI],DX INC SI INC SI DEC CL JNZ DATACHANGE RETIRQ7: DEC BL 。IRQ7中斷程序 JNZ FINISH 。采樣周期到否 MOV DX,300H IN AL,DX 。采樣 SUB AL,80H MOV AH,AL MOV AL,00H MOV DX,NCC MOV Xk,AX CALL ML MOV AX,aYk ADD DX,AX PUSH DX MOV AL,DH MOV DX,302H 。D/A輸出 ADD AL,80H OUT DX,AL POP DX MOV AX,Ba XCHG DX,AX CALL MLFIN: MOV aYk,DX MOV BL,TKFINISH: MOV AL,20H OUT 20H,AL IRETML: CMP DX,7FFFH 。乘法子程序 JA ML1 IMUL DX RETML1: PUSH BX PUSH CX PUSH AX SUB DX,7FFFH IMUL DX MOV BX,DX MOV CX,AX POP AX MOV DX,7FFFH IMUL DX ADD AX,CX ADC DX,BX POP CX POP BX RETSYSINTI: MOV AX,8000h 。系統(tǒng)初始化子程序 OUT 23h,AL XCHG AL,AH OUT 22H,AL OUT 22H,AX MOV DX,0F402H 。int_xcs0 MOV AX,000CH OUT DX,AX MOV DX,0F400H MOV AX,0401H OUT DX,AX MOV DX,0F406H MOV AX,0000H OUT DX,AX MOV DX,0F404H MOV AX,3C01H OUT DX,AX MOV DX,0F822H MOV AL,7FH OUT DX,AL MOV DX,0F824H MOV AL,0B2H OUT DX,AL MOV DX,0F832H MOV AL,0AH OUT DX,AL MOV DX,0F834H MOV AL,1DH OUT DX,AL MOV AL,11H OUT 20H,AL MOV AL,08H OUT 21H,AL MOV AL,04H OUT 21H,AL MOV AL,01H OUT 21H,AL MOV AL,0EFH OUT 21H,AL MOV AL,11H OUT 0A0H,AL MOV AL,30H OUT 0A1H,AL MOV AL,02H OUT 0A1H,AL MOV AL,01H OUT 0A1H,AL MOV AL,0FFH OUT 0A1H,AL RETCODE ENDS END START：PUBLIC TKPUBLIC A1PUBLIC A2PUBLIC A3PUBLIC A4STACK SEGMENT STACK DW 256 DUP(?)STACK ENDSDATA SEGMENTTK DB 01HA1 DB 30HBA1 DW 0000HA2 DB 30HBA2 DW 0000HA3 DB 20HBA3 DW 0000HA4 DB 20HBA4 DW 0000HA2Xk DW 0000HA3Xk_1 DW 0000HA4Xk_2 DW 0000HALLADD DW 0000H Xk DB 00HXXk DB 00HXk_1 DB 00HXk_2 DB 00HDATA ENDSCODE SEGMENT ASSUME CS:CODE, DS:DATASTART: MOV AX,DATA MOV DS,AX PUSH DS MOV AX,0000H MOV DS,AX MOV AX,OFFSET IRQ7 。填寫8259的7號中斷矢量入口地址的偏移量 MOV SI,003CH 。填寫8259中斷7的中段矢量 MOV [SI],AX 。填偏移量矢量 MOV AX,CS 。填寫8259中斷矢量入口地址的段地址 MOV SI,003EH 。填寫7號中斷段地址矢量 MOV [SI],AX POP DS