Improve tuning even further

Signed-off-by: Petr Horacek <[email protected]>
zlosynth · Nov 24, 2024 · b51c3f2 · b51c3f2
1 parent e095f39
commit b51c3f2
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Showing 2 changed files with 136 additions and 130 deletions.
diff --git a/eurorack/src/system/audio.rs b/eurorack/src/system/audio.rs
@@ -2,8 +2,9 @@ use daisy::audio::{self, Block, Interface};
 
 // pub const SAMPLE_RATE: u32 = audio::FS.to_Hz();
 // NOTE: The SAMPLE_RATE needs to be adjusted. Probably because the clock on
-// STM32 is unable to exactly match the speed.
-pub const SAMPLE_RATE: u32 = 47_810;
+// STM32 is unable to exactly match the speed. With this value, it is perfectly
+// in tune on A4.
+pub const SAMPLE_RATE: u32 = 47_793;
 pub const BLOCK_LENGTH: usize = audio::BLOCK_LENGTH;
 
 static mut BUFFER: [(f32, f32); BLOCK_LENGTH] = [(0.0, 0.0); BLOCK_LENGTH];

diff --git a/lib/src/note.rs b/lib/src/note.rs
@@ -131,136 +131,141 @@ pub enum Note {
     G9 = 127,
 }
 
+// NOTE: Generated with Python:
+// ```python
+// for i in range(128):
+//     print("{},".format(440 * 2.0 ** ((i - 12 * 6 + 3) / 12)))
+// ```
 #[allow(clippy::excessive_precision)]
 const FREQUENCIES: [f32; 128] = [
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 #[allow(non_upper_case_globals)]