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@13rac1
Created August 8, 2019 07:24
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Save 13rac1/bb39075f4fcfe6b236be93e2fa5ef935 to your computer and use it in GitHub Desktop.
8 bit Sine Wave lookup array
# Reproduce with Golang
# for x := 0; x < 256; x++ {
# xInRadians := float64(x) / 255 * 2 * math.Pi
# sinX := uint8(math.Round((math.Sin(xInRadians) + 1) / 2 * 255))
# fmt.Printf("%#02x,", sinX)
# if x%8 == 7 {
# fmt.Print("\n")
# }
# }
# Based on https://gist.github.com/funkfinger/965900 but more precise.
uint8_t sine_wave[256] = {
0x80, 0x83, 0x86, 0x89, 0x8c, 0x8f, 0x92, 0x95,
0x98, 0x9c, 0x9f, 0xa2, 0xa5, 0xa8, 0xab, 0xae,
0xb0, 0xb3, 0xb6, 0xb9, 0xbc, 0xbf, 0xc1, 0xc4,
0xc7, 0xc9, 0xcc, 0xce, 0xd1, 0xd3, 0xd5, 0xd8,
0xda, 0xdc, 0xde, 0xe0, 0xe2, 0xe4, 0xe6, 0xe8,
0xea, 0xeb, 0xed, 0xef, 0xf0, 0xf2, 0xf3, 0xf4,
0xf6, 0xf7, 0xf8, 0xf9, 0xfa, 0xfb, 0xfb, 0xfc,
0xfd, 0xfd, 0xfe, 0xfe, 0xfe, 0xff, 0xff, 0xff,
0xff, 0xff, 0xff, 0xff, 0xfe, 0xfe, 0xfd, 0xfd,
0xfc, 0xfc, 0xfb, 0xfa, 0xf9, 0xf8, 0xf7, 0xf6,
0xf5, 0xf4, 0xf2, 0xf1, 0xef, 0xee, 0xec, 0xeb,
0xe9, 0xe7, 0xe5, 0xe3, 0xe1, 0xdf, 0xdd, 0xdb,
0xd9, 0xd7, 0xd4, 0xd2, 0xcf, 0xcd, 0xca, 0xc8,
0xc5, 0xc3, 0xc0, 0xbd, 0xba, 0xb8, 0xb5, 0xb2,
0xaf, 0xac, 0xa9, 0xa6, 0xa3, 0xa0, 0x9d, 0x9a,
0x97, 0x94, 0x91, 0x8e, 0x8a, 0x87, 0x84, 0x81,
0x7e, 0x7b, 0x78, 0x75, 0x71, 0x6e, 0x6b, 0x68,
0x65, 0x62, 0x5f, 0x5c, 0x59, 0x56, 0x53, 0x50,
0x4d, 0x4a, 0x47, 0x45, 0x42, 0x3f, 0x3c, 0x3a,
0x37, 0x35, 0x32, 0x30, 0x2d, 0x2b, 0x28, 0x26,
0x24, 0x22, 0x20, 0x1e, 0x1c, 0x1a, 0x18, 0x16,
0x14, 0x13, 0x11, 0x10, 0x0e, 0x0d, 0x0b, 0x0a,
0x09, 0x08, 0x07, 0x06, 0x05, 0x04, 0x03, 0x03,
0x02, 0x02, 0x01, 0x01, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x01, 0x01, 0x01, 0x02, 0x02,
0x03, 0x04, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,
0x0b, 0x0c, 0x0d, 0x0f, 0x10, 0x12, 0x14, 0x15,
0x17, 0x19, 0x1b, 0x1d, 0x1f, 0x21, 0x23, 0x25,
0x27, 0x2a, 0x2c, 0x2e, 0x31, 0x33, 0x36, 0x38,
0x3b, 0x3e, 0x40, 0x43, 0x46, 0x49, 0x4c, 0x4f,
0x51, 0x54, 0x57, 0x5a, 0x5d, 0x60, 0x63, 0x67,
0x6a, 0x6d, 0x70, 0x73, 0x76, 0x79, 0x7c, 0x7f,
}
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