Fix BufferedGraphicsMode::clear() so that it fills all pixels (#201)

* Fix not all pixels being filled on clear(On)

Currently `clear()` fills the buffer with `0x01` bytes, which represent
7 dark pixels and 1 bright pixel. We want all pixels bright.

Author: zyla

CHANGELOG.md

@@ -7,6 +7,10 @@ SSD1306 monochrome OLED display.
 
 ## [Unreleased] - ReleaseDate
 
+### Fixed
+
+- [#201](https://github.com/jamwaffles/ssd1306/pull/201) Fixed `BufferedGraphicsMode::clear(On)` such that it fills all pixels with `On`, not only some.
+
 ## [0.8.3] - 2023-10-09
 
 ### Changed

src/mode/buffered_graphics.rs

@@ -69,7 +69,7 @@ where
     SIZE: DisplaySize,
 {
     fn clear_impl(&mut self, value: bool) {
-        self.mode.buffer.as_mut().fill(value as u8);
+        self.mode.buffer.as_mut().fill(if value { 0xff } else { 0 });
 
         let (width, height) = self.dimensions();
         self.mode.min_x = 0;