Make a few small updates to support TeXitoi rusty clock (#27)

- add a feature gated alternative full lut for type_a displays
- remove pub from set_lut_helper function
- fix behaviour of set_lut for epd2in9. it always sets the LUT now!
-  better comments

Cargo.toml

@@ -25,6 +25,8 @@ graphics = ["embedded-graphics"]
 epd1in54 = []
 epd2in9 = []
 epd4in2 = []
+# offers an alternative fast full lut for type_a displays, but the refresh isnt as clean looking
+type_a_alternative_faster_lut = []
 
 [dependencies.embedded-graphics]
 optional = true

src/epd2in9/mod.rs

@@ -325,6 +325,7 @@ where
         Ok(())
     }
 
+    /// Set your own LUT, this function is also used internally for set_lut
     fn set_lut_helper(&mut self, spi: &mut SPI, buffer: &[u8]) -> Result<(), SPI::Error> {
         assert!(buffer.len() == 30);
         self.interface

src/traits.rs

@@ -12,6 +12,7 @@ pub(crate) trait Command {
 }
 
 /// Seperates the different LUT for the Display Refresh process
+#[derive(Debug, Clone, PartialEq, Eq)]
 pub enum RefreshLUT {
     /// The "normal" full Lookuptable for the Refresh-Sequence
     FULL,

src/type_a/constants.rs

@@ -1,5 +1,6 @@
-// Original Waveforms from Waveshare
+#[cfg(not(any(feature = "type_a_alternative_faster_lut")))]
 #[rustfmt::skip]
+// Original Waveforms from Waveshare
 pub(crate) const LUT_FULL_UPDATE: [u8; 30] =[
     0x02, 0x02, 0x01, 0x11, 0x12, 0x12, 0x22, 0x22, 
     0x66, 0x69, 0x69, 0x59, 0x58, 0x99, 0x99, 0x88, 
@@ -14,3 +15,11 @@ pub(crate) const LUT_PARTIAL_UPDATE: [u8; 30] =[
     0x00, 0x00, 0x00, 0x00, 0x13, 0x14, 0x44, 0x12, 
     0x00, 0x00, 0x00, 0x00, 0x00, 0x00      
 ];
+
+#[cfg(feature = "type_a_alternative_faster_lut")]
+#[rustfmt::skip]
+// Waveform from TeXiToi/il3820
+pub(crate) const LUT_FULL_UPDATE: [u8; 30] =[
+    0x50, 0xAA, 0x55, 0xAA, 0x11, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0x1F, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+];