[微机实验/TD-PITE] D/A 转换实验+选做实验

Published: at 16:25

ToC

实验内容

编程画出波形，通过 D/A 转换器转换为模拟信号，通过软件示波器观察波形。

实验接线

代码

1
;; DAC0832 IOY0
2
;; BASE OFFSET: 0600H
3
A0832 EQU 0600H
4


5
SSEG SEGMENT STACK
6
  DW 0,0,0,0
7
SSEG ENDS
8


9
CODE SEGMENT
10
ASSUME CS:CODE, SS:SSEG
11


12
START:
13
  MOV DX, A0832
14


15
;; --------- SAW START ---------
16
  MOV CX, 0AH
17
SAW:
18
  MOV AL, 00H
19
JC1:
20
  OUT DX, AL
21
  CALL DELAY_SHORT
22
  CMP AL, 0FFH
23
  JE JC2
24
  INC AL
25
  JMP JC1
26
JC2:
27
  LOOP SAW
28
;; ---------- SAW END ----------
29


30


31
;; --------- RECT START ---------
32
  MOV CX, 02H
33
RECT:
34
  MOV AL, 00H
35
  OUT DX, AL
36
  CALL DELAY_LONG
37
  MOV AL, 0FFH
38
  OUT DX, AL
39
  CALL DELAY_LONG
40
  LOOP RECT
41
;; ---------- RECT END ----------
42


43


44
;; --------- TRI START ---------
45
  MOV CX, 02H
46
TRI:
47
  MOV AL, 00H
48
TR1:
49
  OUT DX, AL
50
  CALL DELAY_SHORT
51
  CMP AL, 0FFH
52
  JE TR2
53
  INC AL
54
  JMP TR1
55
TR2:
56
  OUT DX, AL
57
  CALL DELAY_SHORT
58
  CMP AL, 00H
59
  JE TR3
60
  DEC AL
61
  JMP TR2
62
TR3:
63
  LOOP TRI
64
;; ---------- TRI END ----------
65


66


67
;; --------- STAIR START ---------
68
  MOV CX, 02H
69
STA:
70
  MOV AX, 00H
71
STA1:
72
  OUT DX, AL
73
  CMP AX, 0FFH
74
  JGE STA_FIN
75
  CALL DELAY_LONG
76
  ADD AL, 11H ;; 0FH STAIRS
77
              ;; 11H GAP
78
  JMP STA1
79
STA_FIN:
80
  LOOP STA
81
;; ---------- STAIR END ----------
82


83
  MOV AX, 4C00H
84
  INT 21H
85


86
DELAY_SHORT:
87
  PUSH AX
88
  PUSH CX
89
  MOV CX, 01FFH
90
  LOOP $
91
  POP CX
92
  POP AX
93
  RET
94


95
DELAY_LONG:
96
  PUSH AX
97
  PUSH CX
98
  MOV CX, 0FFFFH
99
  LOOP $
100
  POP CX
101
  POP AX
102
  RET
103


104
CODE ENDS
105
END START

波形

锯齿波、矩形波、三角波
锯齿波、矩形波、三角波

阶梯波
阶梯波

选做实验：中断控制波形

描述

使用单脉冲开关 KK1 在四种波形间进行切换。

分析

将 KK1 与 MIR6 相连，在中断处理程序中判断需要绘制的波形，主循环中绘制实际的波形。

需要封装一下之前用到的波形绘制部分代码。

代码

1
;; DAC0832 IOY0
2
;; BASE OFFSET: 0600H
3
A0832 EQU 0600H
4


5
SSEG SEGMENT STACK
6
  DW 0,0,0,0
7
SSEG ENDS
8


9
CODE SEGMENT
10
ASSUME CS:CODE, SS:SSEG
11


12
START:
13
  ;; MIR6
14
  MOV AX, OFFSET MIR6
15
  MOV SI, 38H
16
  MOV [SI], AX
17
  MOV AX, CS
18
  MOV SI, 3AH
19
  MOV [SI], AX
20


21
  ;; --------------------------------------------------
22
  ;; INIT 8259
23
  CLI
24
  MOV AL, 11H
25
  OUT 20H, AL
26
  MOV AL, 08H
27
  OUT 21H, AL
28
  MOV AL, 04H
29
  OUT 21H, AL
30
  MOV AL, 07H
31
  OUT 21H, AL
32
  MOV AL, 2FH
33
  OUT 21H, AL
34
  STI
35
  ;; --------------------------------------------------
36


37
  MOV DX, A0832
38
  MOV BX, 0
39


40
MAIN:
41
  MOV CX, 1
42
  CMP BX, 0
43
  JE M_SAW
44
  CMP BX, 1
45
  JE M_RECT
46
  CMP BX, 2
47
  JE M_TRI
48
  CALL STA
49
  JMP MAIN
50
M_SAW:
51
  CALL SAW
52
  JMP MAIN
53
M_RECT:
54
  CALL RECT
55
  JMP MAIN
56
M_TRI:
57
  CALL TRI
58
  JMP MAIN
59


60


61
MIR6:
62
  INC BX
63
  CMP BX, 4
64
  JNE BACK
65
  MOV BX, 0
66
BACK:
67
  IRET
68


69
  MOV DX, A0832
70


71


72
SAW:
73
  MOV AL, 00H
74
JC1:
75
  OUT DX, AL
76
  CALL DELAY_SHORT
77
  CMP AL, 0FFH
78
  JE JC2
79
  INC AL
80
  JMP JC1
81
JC2:
82
  LOOP SAW
83
  RET
84


85


86
RECT:
87
  MOV AL, 00H
88
  OUT DX, AL
89
  CALL DELAY_LONG
90
  MOV AL, 0FFH
91
  OUT DX, AL
92
  CALL DELAY_LONG
93
  LOOP RECT
94
  RET
95


96


97
TRI:
98
  MOV AL, 00H
99
TR1:
100
  OUT DX, AL
101
  CALL DELAY_SHORT
102
  CMP AL, 0FFH
103
  JE TR2
104
  INC AL
105
  JMP TR1
106
TR2:
107
  OUT DX, AL
108
  CALL DELAY_SHORT
109
  CMP AL, 00H
110
  JE TR3
111
  DEC AL
112
  JMP TR2
113
TR3:
114
  LOOP TRI
115
  RET
116


117


118
STA:
119
  MOV AX, 00H
120
STA1:
121
  OUT DX, AL
122
  CMP AX, 0FFH
123
  JGE STA_FIN
124
  CALL DELAY_LONG
125
  ADD AL, 11H ;; 0FH STAIRS
126
              ;; 11H GAP
127
  JMP STA1
128
STA_FIN:
129
  LOOP STA
130
  RET
131


132


133
DELAY_SHORT:
134
  PUSH AX
135
  PUSH CX
136
  MOV CX, 01FFH
137
  LOOP $
138
  POP CX
139
  POP AX
140
  RET
141


142
DELAY_LONG:
143
  PUSH AX
144
  PUSH CX
145
  MOV CX, 0FFFFH
146
  LOOP $
147
  POP CX
148
  POP AX
149
  RET
150


151
CODE ENDS
152
END START