Add documentation

README.md

@@ -45,6 +45,7 @@ epd.display_frame(&mut spi)?;
 | [1.54 Inch B/W (A)](https://www.waveshare.com/1.54inch-e-Paper-Module.htm) | Black, White | ✕ | ✔ | ✔ | ✔ |
 | [2.13 Inch B/W (A)](https://www.waveshare.com/product/2.13inch-e-paper-hat.htm) | Black, White | ✕ | ✔ |  |  |
 | [2.9 Inch B/W (A)](https://www.waveshare.com/product/2.9inch-e-paper-module.htm) | Black, White | ✕ | ✔ | ✔ | ✔ [[2](#2-29-inch-e-ink-blackwhite---tests)] |
+| [1.54 Inch B/W/R (B)](https://www.waveshare.com/product/modules/oleds-lcds/e-paper/1.54inch-e-paper-module-b.htm) | Black, White, Red | ✕ | ✕ | ✔ | ✔ |
 
 
 ### [1]: 4.2 Inch E-Ink Black/White - Partial Refresh

src/epd1in54b/mod.rs

@@ -1,3 +1,5 @@
+//! A simple Driver for the Waveshare 1.54" (B) E-Ink Display via SPI
+
 use embedded_hal::{
     blocking::{delay::*, spi::Write},
     digital::*,

src/traits.rs

@@ -52,6 +52,8 @@ where
     ) -> Result<(), SPI::Error>;
 }
 
+
+/// Functions to interact with two color panels
 pub trait WaveshareTwoColorDisplay<SPI, CS, BUSY, DC, RST>:
     WaveshareDisplay<SPI, CS, BUSY, DC, RST>
 where
@@ -61,6 +63,7 @@ where
     DC: OutputPin,
     RST: OutputPin,
 {
+    /// Update both color planes
     fn update_both_planes(
         &mut self,
         spi: &mut SPI,