微机原理及接口技术音乐发生器实验
微机原理及接口技术音乐发生器实验发生器音乐发生器))
Y
N
N
(图2.2.1)
符号－频率对照表：
音符1 2 3 4 5 6 7频率131 147 165 175 196 220 247音符1 2 3 4 5 6 7 1(高)频率262 294 330 349 392 440 494 523 (3.2.1)
3.2.2音符的持续时间要根据乐曲的速度及每个音符的节拍数来确定。在4/4拍中，四分音符为1拍，每小节4拍，全音符持续4拍，二分音符持续2拍，四分音符持续1拍，八分音符持续半拍。如果给全音符分配1秒的时间，则二分音符的持续时间为0.5秒，四分音符的持续时间为0.25秒，八分音符的持续时间为0.125秒。
音符-延时对照表
音符全音符二分音符四分音符八分音符时间1760ms880ms440ms220ms倍数321684
3.2.3程序设计：
sstack segment stack
dw 200 dup(?)
sstack ends
data segment
bg db 'Two tigers ...'
db 0ah,0dh
db 'press any key to stop! ',0ah,0dh,'$'
freq dw 494,440,392,349,262,262,392, 440,392, 392,349
dw 494,440,392,349,262,262, 349, 349,330,262,220,262
dw 262,294,175,196,220,175, 175,196, 175,165, 175, 175
dw 175, 175,262,262,175,165,220,220,196,175,165
dw 175,394,175,196,220,175,220,247,220,175,131,165
dw 175,262,262,220,220,247262,247,220,175,196,220
dw 220,175,220,394,330,330,330,349,330,262,220,294,294
dw 175,220,349,330,330,349,392,392,349,349,392,440,392,392,349
dw 330,349,349,349,349,330,330,349,392,262,523,523,523
dw 131,440,392,440,392,392,349,392,392,392,440,349,330,349
dw 349,440,392,440,392,349,392,392,392,392,440,349,330,349
dw 349,440,392,440,392,349,392,440,494,523,523,494,440,392, 349
dw330,349,392,440,349,294,392,330,349,349,440,392,440,392,392,349, 392
dw392,440,349,330,349,349,440,440,349,392,440,494,523,523,523,494,349
dw 440,392,349,330,349,392,440,349,523,262,494,440,349,392,392,349
time dw 16,8,8,8,4,8,32,16,8,8,32
dw 16,8,8,8,4,4,8,8,8,16,16,24,
dw 16,8,8,8,4,16,8,4,24,8,4,4,32
dw 16,8,8,8,4,8,32,16,8,8,32
dw 16,8,8,8,4,4,8,8,8,16,16,24
dw 16,16,8,4,16,8,4,4,8,4,4,32
dw 16,8,8,8,4,8,
