Add firmware without white key quantization

Due to white key quantization, the module is quite sensitive to
inaccurate CV input of TONE. This is especially notable when the same CV
is simultaneously used to control the pitch of another module as well.

This patch adds a feature flag `even_quantization`. If this is enabled,
white key quantization is switched off.

Signed-off-by: Petr Horacek <[email protected]>

CHANGELOG.md

@@ -7,6 +7,7 @@ backwards compatibility.
 ## Unreleased
 
 * Pure Data externals were moved to a [dedicated project](https://github.com/zlosynth/automaton).
+* Offer alternative firmware with white key quantization disabled.
 
 ## 2.2.1
 

eurorack/Cargo.toml

@@ -35,3 +35,6 @@ opt-level = "z" # This contains code used only during the boot, no need for spee
 
 [profile.release.package.crc]
 opt-level = "z" # CRC is only used while restoring a config on boot and does not need to be fast
+
+[features]
+even_quantization = ["achordion-lib/even_quantization"]

hack/release.sh

@@ -17,6 +17,7 @@ rm -rf release
 mkdir release
 
 pushd eurorack && cargo +1.63.0 objcopy --release -- -O binary ../release/achordion-firmware-${version}.bin && popd
+pushd eurorack && cargo +1.63.0 objcopy --release --features even_quantization -- -O binary ../release/achordion-firmware-${version}-even-quantization.bin && popd
 
 make manual
 cp manual/user/manual_digital.pdf release/achordion-user-manual.pdf

hack/release.tmpl.md

@@ -5,3 +5,7 @@ ${CHANGES}
 ## Firmware
 
 Achordion's firmware can be upgraded to obtain new features and bug-fixes. To do so, download the binary from attachments bellow, navigate to [Electro-Smith's web programmer](https://electro-smith.github.io/Programmer/) and follow the guide described under the "Display Help" button.
+
+## Known issues
+
+Due to white key quantization, the module is quite sensitive to inaccurate CV input of TONE. This is especially notable when the same CV is simultaneously used to control the pitch of another module as well. If you suffer from these issues, try the alternative firmware `achordion-firmware-x.y.z-even-quantization.bin`.

lib/Cargo.toml

@@ -13,6 +13,7 @@ publish = false
 default = ["stable_amplitude"]
 balanced_amplitude = []
 stable_amplitude = []
+even_quantization = []
 
 [dependencies]
 micromath = "1.1"

lib/src/note.rs

@@ -326,6 +326,11 @@ impl Note {
         Self::try_from_i16(note as i16).unwrap()
     }
 
+    #[inline(always)]
+    pub fn try_from_u8(note: u8) -> Option<Note> {
+        Self::try_from_i16(note as i16)
+    }
+
     #[inline(always)]
     pub fn try_from_i16(note: i16) -> Option<Note> {
         if note >= 0 && note <= Note::HIGHEST_NOTE as i16 {