C 16位微控制器上的正弦函数

我需要生成一个正弦波来填充1024大小的字符表。微控制器上的字大小为16位，浮点操作不可用

正弦波本身将在0到255之间振荡，127为中心点

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有什么想法吗？

您实际上只需要存储四分之一的正弦波——您可以从第一象限查找其他四分之三的正弦波。因此，您只需要256个字节

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要在微控制器上生成值，请执行。您可以存储一个值，并由此生成整个正弦波

在您的电脑上创建一个预计算数组。如果ROM（或等效的，如闪存或代码段）空间非常宝贵，您只需创建数组的四分之一，然后将这部分镜像到数组的其他768字节。

使用float以您喜欢的语言编写一个sin表生成器。
将结果缩放并四舍五入到所需的范围1024/-127..+128（您可以立即执行此操作）。 从表中，用ASM或C生成一个源文件，哪种方式更适合您。
确保生成的表在C中标记为“const”，或转到ASM中的适当部分，使其转到闪存而不是RAM。
在项目中包含该文件

现在intsin（x）1是：

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您可以通过仅将表格用于第一个象限来提高分辨率。也可以仅使用正值（0..255）。然后您的intsin（x）将需要确定象限并镜像第一个象限的结果。

您只需在PC上生成表格并在MCU上使用即可。正如有人所说，您只需要四个句点，但要完整地回答您的问题，以下是所有1024个字符：

  for k := 0 to 1023 do
      buffer[k] := (round(128+127*sin(2*pi*k/1024)));


128, 129, 130, 130, 131, 132, 133, 133, 134, 135, 136, 137, 137, 138, 139, 140, 140, 
141, 142, 143, 144, 144, 145, 146, 147, 147, 148, 149, 150, 150, 151, 152, 153, 
154, 154, 155, 156, 157, 157, 158, 159, 160, 160, 161, 162, 163, 163, 164, 165, 
166, 166, 167, 168, 169, 169, 170, 171, 172, 172, 173, 174, 174, 175, 176, 177, 
177, 178, 179, 179, 180, 181, 182, 182, 183, 184, 184, 185, 186, 186, 187, 188, 
189, 189, 190, 191, 191, 192, 193, 193, 194, 195, 195, 196, 197, 197, 198, 199, 
199, 200, 200, 201, 202, 202, 203, 204, 204, 205, 206, 206, 207, 207, 208, 209, 
209, 210, 210, 211, 212, 212, 213, 213, 214, 214, 215, 216, 216, 217, 217, 218, 
218, 219, 219, 220, 221, 221, 222, 222, 223, 223, 224, 224, 225, 225, 226, 226, 
227, 227, 228, 228, 229, 229, 230, 230, 230, 231, 231, 232, 232, 233, 233, 234, 
234, 234, 235, 235, 236, 236, 237, 237, 237, 238, 238, 239, 239, 239, 240, 240, 
240, 241, 241, 241, 242, 242, 242, 243, 243, 243, 244, 244, 244, 245, 245, 245, 
246, 246, 246, 246, 247, 247, 247, 248, 248, 248, 248, 249, 249, 249, 249, 250, 
250, 250, 250, 250, 251, 251, 251, 251, 251, 252, 252, 252, 252, 252, 252, 253, 
253, 253, 253, 253, 253, 253, 254, 254, 254, 254, 254, 254, 254, 254, 254, 254, 
254, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 254, 254, 
254, 254, 254, 254, 254, 254, 254, 254, 254, 253, 253, 253, 253, 253, 253, 253, 
252, 252, 252, 252, 252, 252, 251, 251, 251, 251, 251, 250, 250, 250, 250, 250, 
249, 249, 249, 249, 248, 248, 248, 248, 247, 247, 247, 246, 246, 246, 246, 245, 
245, 245, 244, 244, 244, 243, 243, 243, 242, 242, 242, 241, 241, 241, 240, 240, 
240, 239, 239, 239, 238, 238, 237, 237, 237, 236, 236, 235, 235, 234, 234, 234, 
233, 233, 232, 232, 231, 231, 230, 230, 230, 229, 229, 228, 228, 227, 227, 226, 
226, 225, 225, 224, 224, 223, 223, 222, 222, 221, 221, 220, 219, 219, 218, 218, 
217, 217, 216, 216, 215, 214, 214, 213, 213, 212, 212, 211, 210, 210, 209, 209, 
208, 207, 207, 206, 206, 205, 204, 204, 203, 202, 202, 201, 200, 200, 199, 199, 
198, 197, 197, 196, 195, 195, 194, 193, 193, 192, 191, 191, 190, 189, 189, 188, 
187, 186, 186, 185, 184, 184, 183, 182, 182, 181, 180, 179, 179, 178, 177, 177, 
176, 175, 174, 174, 173, 172, 172, 171, 170, 169, 169, 168, 167, 166, 166, 165, 
164, 163, 163, 162, 161, 160, 160, 159, 158, 157, 157, 156, 155, 154, 154, 153, 
152, 151, 150, 150, 149, 148, 147, 147, 146, 145, 144, 144, 143, 142, 141, 140, 
140, 139, 138, 137, 137, 136, 135, 134, 133, 133, 132, 131, 130, 130, 129, 128, 
127, 126, 126, 125, 124, 123, 123, 122, 121, 120, 119, 119, 118, 117, 116, 116, 
115, 114, 113, 112, 112, 111, 110, 109, 109, 108, 107, 106, 106, 105, 104, 103, 
102, 102, 101, 100, 99, 99, 98, 97, 96, 96, 95, 94, 93, 93, 92, 91, 
90, 90, 89, 88, 87, 87, 86, 85, 84, 84, 83, 82, 82, 81, 80, 79, 
79, 78, 77, 77, 76, 75, 74, 74, 73, 72, 72, 71, 70, 70, 69, 68, 
67, 67, 66, 65, 65, 64, 63, 63, 62, 61, 61, 60, 59, 59, 58, 57, 
57, 56, 56, 55, 54, 54, 53, 52, 52, 51, 50, 50, 49, 49, 48, 47, 
47, 46, 46, 45, 44, 44, 43, 43, 42, 42, 41, 40, 40, 39, 39, 38, 
38, 37, 37, 36, 35, 35, 34, 34, 33, 33, 32, 32, 31, 31, 30, 30, 
29, 29, 28, 28, 27, 27, 26, 26, 26, 25, 25, 24, 24, 23, 23, 22, 
22, 22, 21, 21, 20, 20, 19, 19, 19, 18, 18, 17, 17, 17, 16, 16, 
16, 15, 15, 15, 14, 14, 14, 13, 13, 13, 12, 12, 12, 11, 11, 11, 
10, 10, 10, 10, 9, 9, 9, 8, 8, 8, 8, 7, 7, 7, 7, 6, 
6, 6, 6, 6, 5, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 3, 
3, 3, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 
2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 
2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 
4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 
7, 7, 7, 7, 8, 8, 8, 8, 9, 9, 9, 10, 10, 10, 10, 11, 
11, 11, 12, 12, 12, 13, 13, 13, 14, 14, 14, 15, 15, 15, 16, 16, 
16, 17, 17, 17, 18, 18, 19, 19, 19, 20, 20, 21, 21, 22, 22, 22, 
23, 23, 24, 24, 25, 25, 26, 26, 26, 27, 27, 28, 28, 29, 29, 30, 
30, 31, 31, 32, 32, 33, 33, 34, 34, 35, 35, 36, 37, 37, 38, 38, 
39, 39, 40, 40, 41, 42, 42, 43, 43, 44, 44, 45, 46, 46, 47, 47, 
48, 49, 49, 50, 50, 51, 52, 52, 53, 54, 54, 55, 56, 56, 57, 57, 
58, 59, 59, 60, 61, 61, 62, 63, 63, 64, 65, 65, 66, 67, 67, 68, 
69, 70, 70, 71, 72, 72, 73, 74, 74, 75, 76, 77, 77, 78, 79, 79, 
80, 81, 82, 82, 83, 84, 84, 85, 86, 87, 87, 88, 89, 90, 90, 91, 
92, 93, 93, 94, 95, 96, 96, 97, 98, 99, 99, 100, 101, 102, 102, 103, 
104, 105, 106, 106, 107, 108, 109, 109, 110, 111, 112, 112, 113, 114, 115, 116, 
116, 117, 118, 119, 119, 120, 121, 122, 123, 123, 124, 125, 126, 126, 127

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能否在主机上生成该表并将其存储为常量表？然后将其链接到@mtrw 256值？我想我可以从电脑上的程序生成C代码。不过，我正在寻找一个有效的算法。当然，我会考虑这个更容易的选择。谢谢。我不明白需要一个算法。如果你有一张桌子，你已经接受了空格键。如果在运行时或链接时初始化空间，则没有区别。但是如果你根本不想要一个表，那么是的，你需要一个算法。mtrw，我有点同意你的看法，但可能是他的闪光灯很少，但内存更多。那么太空打击就不重要了。否则，不使用数组就很奇怪…：）mtrw，对于1024或256字节的阵列，您是否有很少的闪存可用？请记住，CORDIC实现也会占用一些空间…@AmigableClarkKant-Heh，是的，我可能应该解决它。我知道它就在那个订单上的某个地方。我是说，他说1024个字符。：-）@AmigableClarkKant是的，我只是扫描了一下，没有读，我知道这是关于在微控制器上生成正弦函数的。@AmigableClarkKant在任何情况下，确切的数字其实并不重要——更多的是关于如何生成和存储正弦函数的想法wave@AnthonyBlake谢谢，我在找一个算法。

  for k := 0 to 1023 do
      buffer[k] := (round(128+127*sin(2*pi*k/1024)));


128, 129, 130, 130, 131, 132, 133, 133, 134, 135, 136, 137, 137, 138, 139, 140, 140, 
141, 142, 143, 144, 144, 145, 146, 147, 147, 148, 149, 150, 150, 151, 152, 153, 
154, 154, 155, 156, 157, 157, 158, 159, 160, 160, 161, 162, 163, 163, 164, 165, 
166, 166, 167, 168, 169, 169, 170, 171, 172, 172, 173, 174, 174, 175, 176, 177, 
177, 178, 179, 179, 180, 181, 182, 182, 183, 184, 184, 185, 186, 186, 187, 188, 
189, 189, 190, 191, 191, 192, 193, 193, 194, 195, 195, 196, 197, 197, 198, 199, 
199, 200, 200, 201, 202, 202, 203, 204, 204, 205, 206, 206, 207, 207, 208, 209, 
209, 210, 210, 211, 212, 212, 213, 213, 214, 214, 215, 216, 216, 217, 217, 218, 
218, 219, 219, 220, 221, 221, 222, 222, 223, 223, 224, 224, 225, 225, 226, 226, 
227, 227, 228, 228, 229, 229, 230, 230, 230, 231, 231, 232, 232, 233, 233, 234, 
234, 234, 235, 235, 236, 236, 237, 237, 237, 238, 238, 239, 239, 239, 240, 240, 
240, 241, 241, 241, 242, 242, 242, 243, 243, 243, 244, 244, 244, 245, 245, 245, 
246, 246, 246, 246, 247, 247, 247, 248, 248, 248, 248, 249, 249, 249, 249, 250, 
250, 250, 250, 250, 251, 251, 251, 251, 251, 252, 252, 252, 252, 252, 252, 253, 
253, 253, 253, 253, 253, 253, 254, 254, 254, 254, 254, 254, 254, 254, 254, 254, 
254, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 
255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 254, 254, 
254, 254, 254, 254, 254, 254, 254, 254, 254, 253, 253, 253, 253, 253, 253, 253, 
252, 252, 252, 252, 252, 252, 251, 251, 251, 251, 251, 250, 250, 250, 250, 250, 
249, 249, 249, 249, 248, 248, 248, 248, 247, 247, 247, 246, 246, 246, 246, 245, 
245, 245, 244, 244, 244, 243, 243, 243, 242, 242, 242, 241, 241, 241, 240, 240, 
240, 239, 239, 239, 238, 238, 237, 237, 237, 236, 236, 235, 235, 234, 234, 234, 
233, 233, 232, 232, 231, 231, 230, 230, 230, 229, 229, 228, 228, 227, 227, 226, 
226, 225, 225, 224, 224, 223, 223, 222, 222, 221, 221, 220, 219, 219, 218, 218, 
217, 217, 216, 216, 215, 214, 214, 213, 213, 212, 212, 211, 210, 210, 209, 209, 
208, 207, 207, 206, 206, 205, 204, 204, 203, 202, 202, 201, 200, 200, 199, 199, 
198, 197, 197, 196, 195, 195, 194, 193, 193, 192, 191, 191, 190, 189, 189, 188, 
187, 186, 186, 185, 184, 184, 183, 182, 182, 181, 180, 179, 179, 178, 177, 177, 
176, 175, 174, 174, 173, 172, 172, 171, 170, 169, 169, 168, 167, 166, 166, 165, 
164, 163, 163, 162, 161, 160, 160, 159, 158, 157, 157, 156, 155, 154, 154, 153, 
152, 151, 150, 150, 149, 148, 147, 147, 146, 145, 144, 144, 143, 142, 141, 140, 
140, 139, 138, 137, 137, 136, 135, 134, 133, 133, 132, 131, 130, 130, 129, 128, 
127, 126, 126, 125, 124, 123, 123, 122, 121, 120, 119, 119, 118, 117, 116, 116, 
115, 114, 113, 112, 112, 111, 110, 109, 109, 108, 107, 106, 106, 105, 104, 103, 
102, 102, 101, 100, 99, 99, 98, 97, 96, 96, 95, 94, 93, 93, 92, 91, 
90, 90, 89, 88, 87, 87, 86, 85, 84, 84, 83, 82, 82, 81, 80, 79, 
79, 78, 77, 77, 76, 75, 74, 74, 73, 72, 72, 71, 70, 70, 69, 68, 
67, 67, 66, 65, 65, 64, 63, 63, 62, 61, 61, 60, 59, 59, 58, 57, 
57, 56, 56, 55, 54, 54, 53, 52, 52, 51, 50, 50, 49, 49, 48, 47, 
47, 46, 46, 45, 44, 44, 43, 43, 42, 42, 41, 40, 40, 39, 39, 38, 
38, 37, 37, 36, 35, 35, 34, 34, 33, 33, 32, 32, 31, 31, 30, 30, 
29, 29, 28, 28, 27, 27, 26, 26, 26, 25, 25, 24, 24, 23, 23, 22, 
22, 22, 21, 21, 20, 20, 19, 19, 19, 18, 18, 17, 17, 17, 16, 16, 
16, 15, 15, 15, 14, 14, 14, 13, 13, 13, 12, 12, 12, 11, 11, 11, 
10, 10, 10, 10, 9, 9, 9, 8, 8, 8, 8, 7, 7, 7, 7, 6, 
6, 6, 6, 6, 5, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 3, 
3, 3, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 
2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 
2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 
4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 
7, 7, 7, 7, 8, 8, 8, 8, 9, 9, 9, 10, 10, 10, 10, 11, 
11, 11, 12, 12, 12, 13, 13, 13, 14, 14, 14, 15, 15, 15, 16, 16, 
16, 17, 17, 17, 18, 18, 19, 19, 19, 20, 20, 21, 21, 22, 22, 22, 
23, 23, 24, 24, 25, 25, 26, 26, 26, 27, 27, 28, 28, 29, 29, 30, 
30, 31, 31, 32, 32, 33, 33, 34, 34, 35, 35, 36, 37, 37, 38, 38, 
39, 39, 40, 40, 41, 42, 42, 43, 43, 44, 44, 45, 46, 46, 47, 47, 
48, 49, 49, 50, 50, 51, 52, 52, 53, 54, 54, 55, 56, 56, 57, 57, 
58, 59, 59, 60, 61, 61, 62, 63, 63, 64, 65, 65, 66, 67, 67, 68, 
69, 70, 70, 71, 72, 72, 73, 74, 74, 75, 76, 77, 77, 78, 79, 79, 
80, 81, 82, 82, 83, 84, 84, 85, 86, 87, 87, 88, 89, 90, 90, 91, 
92, 93, 93, 94, 95, 96, 96, 97, 98, 99, 99, 100, 101, 102, 102, 103, 
104, 105, 106, 106, 107, 108, 109, 109, 110, 111, 112, 112, 113, 114, 115, 116, 
116, 117, 118, 119, 119, 120, 121, 122, 123, 123, 124, 125, 126, 126, 127