微机原理编程题.doc

微机原理编程题1. 分支程序设计.编写一段程序，已知BUF1单元中有一带符号字节数据X，BUF2中有一带符号字节数据Y，根据以下函数关系编写程序求Z的值，结果存入RESULT 单元。Z=|X-Y|；DATA SEGMENTBUF1 DB 05HBUF2 DB 02HRESULT DB ?DATA ENDSCODE SEGMENT ASSUME CS:CODE,DS:DATASTART:MOV AX,DATA MOV DS,AX MOV AL,BUF1 MOV BL,BUF2 SUB AL,BL JNC GREAT NEG ALGREAT:MOV RESULT,ALEXIT: MOV AH,4CH INT 21H CODE ENDS END START .编写一段程序，已知BUF单元中有一无符号字节数据X，假设为8，根据以下函数关系编写程序求Y的值，结果存入RESULT 单元。Z=5X X=10;DATA SEGMENTBUF DB 8RESULT DB ?DATA ENDSCODE SEGMENTASSUME CS:CODE,DS:DATASTART:MOV AX,DATA MOV DS,AX MOV AL,BUF CMP AL,10 JAE GRE MOV BL,AL ADD AL,AL ADD AL,AL ADD AL,BL JMP DONEGRE: SUB AL,5DONE: MOV RESULT,AL MOV AH,4CH INT 21H CODE ENDS END START.在内存单元BUF中存放一个带符号字节数据X，假定为-2，试根据以下函数关系编写程序求Y的值，结果存入RESULT 单元。Y=1 X0,0 X=0,-1 X0;DATA SEGMENTBUF DB -2RESULT DB ?DATA ENDSCODE SEGMENT ASSUME CS:CODE,DS:DATASTART: MOV AX,DATA MOV DS,AX MOV AL,BUF CMP AL,0 JGE L1 MOV AL,-1 JMP L3L1:JZ L2 MOV AL,1 JMP L3L2:MOV AL,0L3:MOV RESULT,AL MOV AH,4CH INT 21HCODE ENDS END START 2. N个数中求最大值、最小值.假定N=10,已知原始数据存放在BUF开始的内存单元中，将结果存入MAX，MIN内存单元中。DATA SEGMENTBUF DB 3,5,7,8,5,3,9,7,13,1COUNT EQU $-BUFMAX DB ?MIN DB ? DATA ENDSCODE SEGMENTASSUME CS:CODE,DS:DATASTART: MOV AX,DATA MOV DS,AX MOV CX,COUNT-1 MOV AL,BUF MOV MAX,AL MOV MIN,AL LEA SI,BUFAGAIN: MOV AL,SI+1CMP AL,MINJGE S1MOV MIN,ALS1:CMP AL,MAXJLE S2MOV MAX,ALS2: INC SI LOOP AGAIN MOV AH,4CH INT 21HCODE ENDS END START 3. 编写程序求1+2+3+N100时最大的N值，将N值送NUM单元中，同时将1+2+3+N的和送到SUM单元中。DATA SEGMENTNUM DB ?SUM DB ?DATA ENDSCODE SEGMENT ASSUME CS:CODE,DS:DATASTART:MOV AX,DATA MOV DS,AX MOV AL,0 MOV BL,0AGAIN:INC BL ADD AL,BL CMP AL,100 JB AGAIN SUB AL,BL DEC BL MOV NUM,BL MOV SUM,AL MOV AH,4CH INT 21H CODE ENDS END START 4. 统计字符，正数，负数，零的个数。若自STRING单元开始存放一个字符串，以$结尾，试编写程序，统计字符串的长度，并将结果存入COUNT单元。DATA SEGMENTSTRING DB abcdefg$COUNT DW ?DATA ENDSCODE SEGMENTASSUME CS:CODE,DS:DATASTART:MOV AX,DATA MOV DS,AX LEA SI,STRING MOV CX,0NEXT: MOV AL,SI CMP AL,$ JZ DONE INC CX INC SI JMP NEXTDONE: MOV COUNT,CX MOV AH,4CH INT 21H CODE ENDS END START .自BUF单元开始存放10个带符号字节数据，将其中的正数、负数和零选出来，并统计其个数，分别存入PLUS、MINUS和ZERO单元中。DATA SEGMENTBUF DB 5,-2,0,-1,4,0,-4,8,0,-7PLUS DB ?MINUS DB ?ZERO DB ?DATA ENDSCODE SEGMENTASSUME CS:DATA,DS:DATASTART:MOV AX,DATA MOV DS,AX LEA SI,BUF MOV CX,10AGAIN:MOV AL,BX INC BX AND AL,AL JS M1 JZ M2 INC PLUS JMP NEXTM1: INC MINUS JMP NEXTM2: INC ZERO JMP NEXTNEXT: LOOP AGAIN MOV AH,4CH INT 21H CODE ENDS END START 5. 求压缩BCD码的和。已知从BUF1和BUF2单元开始，存放两个各为10个字节的BCD数，求这两个数的和，并将结果存入BUF3单元中。DATA SEGMENTBUF1 DB 01H,01H,01H,01H,01H,01H,01H,01H,01H,01HBUF2 DB 03H,03H,03H,03H,03H,03H,03H,03H,03H,03HBUF3 DB 11 DUP(?) DATA ENDSCODE SEGMENT ASSUME CS:CODE,DS:DATASTART: MOV AX,DATA MOV DS,AX MOV CX,10 LEA SI,BUF1 LEA DI,BUF2 LEA BX,BUF3AGAIN: MOV AL,SI ADC AL,DI DAA MOV BX,AL INC SI INC DI INC BX LOOP AGAIN ADC AH,0 MOV BX,AH MOV AH,4CH INT 21HCODE ENDSEND START6. 8255编程题：(课后实验) 8255工作于方式0，此时PA、PB、PC均为可独立输入/输出的并行口。8255的各寄存器对应的口地址为：PA口：200H，PB口：202H，PC口：204H，控制口：206H。要求8255工作于方式0，PA口设置为输入，PC口设置为输出。DATA SEGMENTC8255 EQU 206HP8255A EQU 200HP8255C EQU 204HDATA ENDSCODE SEGMENTASSUME