习题五（第5章）（2）
1．方式0 A出B入，开关Si闭合时PBi=1, PAi=0低电平时继电器Ri吸合INIT: MOV AL,1000X01XB
MOV DX,63H
OUT DX,AL
MOV AL,0
MOV DX,60H
OUT DX,AL
;10ms：
MOV AL,CTRLbyte
MOV DX,60H ‘;PA
OUT DX,AL
INC DX
IN AL,DX
MOV Sbyte,AL
2．（1)MOV AL,10010010B
MOV DX,0063H
OUT DX,AL
(2)MOV AL,11XXX10XB
(3)MOV AL,10110111H
3．除数=0060H
MOV DX, 02C0H+3
MOV AL, 80H
OUT DX, AL
MOV DX, 02C1H
MOV AL, 0
OUT DX, AL
DEC DX ; (MOV DX, 2C0H)
MOV AL, 60H
OUT DX, AX
MOV DX, 2C0+3
MOV AL, 00001010B (0AH) ；波特率
OUT DX, AL
MOV DX, 2C1H ;中断允许
MOV AL, 00000010B
OUT DX, AL
3. 除数=0030H
波特率字=00000011B=03H
设串口基址3F8H
可用查询或中断方式，查询可查询缓冲区
查询：MOV DX, 3FBH
MOV AL, 80H
OUT DX, AL
MOV DX, 3F9H
MOV AL, 0
OUT DX, AL
MOV DX, 3F8H
MOV AL, 30H
OUT DX, AL
; 发送：
T1: MOV DX, 3FDH
IN AL, DX
TEST AL, 20H
JZ T1
MOV AL, 0AAH
MOV DX, 3F8H
OUT DX, AL
CALL SREGCK
MOV AL, 55H
MOV DX, 3F8H
OUT DX, AL
CALL SREGCK
MOV CL, T_LEN
MOV SI,OFFSET T_BUF
TLOOP: MOV AL, [SI]
MOV DX, 3F8H
OUT DX, AL
CALL SREGCK
INC SI
DEC CL
JNE TLOOP
MOV AL, 55H
CALL TSEND
MOV AL, 0AAH
CALL TSEND
…………
发送查询子程序
SREGCK: DX, 3FDH
IN AL, DX
TEST AL, 20H
JZ SREGCK
RET
发送子程序
TSEND: MOV DX, 3F8H
OUT DX, AL
RET
接收：
R1: CALL RBUFCK
MOV DX, 3F8H
IN AL, DX
CMP AL, 0AAH
JNZ R1
CALL BRICV ;AAH
CMP AL, 55H
JNZ R1
MOV AL, 0 ;AAH,55H,启动计数MOV R_LEN, AL
MOV SI,OFFSET R_BUF
R2: CALL BRICV
CMP AL, 55H
JZ R3
MOV [SI], AL
INC R_LEN
INC SI
JMP R2
R3: CALL BRICV
CMP AL, 0AAH
JZ R4 ;55H,AAH
MOV AL, 0FFH
MOV ERROR, AL
…….
R4: MOV AL, 00
MOV ERROR, AL
…………
接收查询子程序
RBUFCK: MOV DX, 3FDH
IN AL, DX
TEST AL, 01
JZ RBUFCK
RET
接收子程序
BRICV: MOV DX, 3F8H
IN AL, DX
RET
4．
MOV AL, 4
MOV DX, 600H+8
OUT DX, AL
MOV AL, 0
MOV DX, 600H+0DH
OUT DX, AL
MOV DX, 600H+2H
MOV AX, OFFSET SOURCC
OUT DX, AL
MOV AL, AH
OUT DX, AL
MOV AX, 1000H
MOV DX, 0600H+3 ;1#字节数
OUT DX, AL
MOV AL, AH
OUT DX, AL
MOV DX, 0600H+0BH ；模式R MOV AL, 00001001B ；READ OUT DX, AL
MOV AX, OFFSET DST
MOV DX, 0600H+4 ；2#地址OUT DX, AL
MOV AL, AH
OUT DX, AL
MOV AX, 1000H
MOV DX, 0600H+5 ；2#字节数OUT DX, AL
MOV AL, AH
OUT DX, AL
