1 files changed, 95 insertions, 0 deletions
diff --git a/sw/deps/hd44780-driver/src/display_mode.rs b/sw/deps/hd44780-driver/src/display_mode.rs
new file mode 100644
index 0000000..8039f7b
--- /dev/null
+++ b/sw/deps/hd44780-driver/src/display_mode.rs
@@ -0,0 +1,95 @@
+use crate::{Cursor, CursorBlink, Display};
+
+pub struct DisplayMode {
+    pub cursor_visibility: Cursor,
+    pub cursor_blink: CursorBlink,
+    pub display: Display,
+}
+
+impl Default for DisplayMode {
+    fn default() -> DisplayMode {
+        DisplayMode {
+            cursor_visibility: Cursor::Visible,
+            cursor_blink: CursorBlink::On,
+            display: Display::On,
+        }
+    }
+}
+
+impl DisplayMode {
+    pub fn as_byte(&self) -> u8 {
+        let cursor_blink_bits = match self.cursor_blink {
+            CursorBlink::On => 0b0000_0001,
+            CursorBlink::Off => 0,
+        };
+
+        let cursor_visible_bits = match self.cursor_visibility {
+            Cursor::Visible => 0b0000_0010,
+            Cursor::Invisible => 0,
+        };
+
+        let display_bits = match self.display {
+            Display::On => 0b0000_0100,
+            Display::Off => 0,
+        };
+
+        0b0000_1000 | cursor_visible_bits | cursor_blink_bits | display_bits
+    }
+}
+
+#[cfg(test)]
+mod tests {
+
+    use super::*;
+
+    #[test]
+    fn cursor_visible() {
+        let dm = DisplayMode {
+            cursor_visibility: Cursor::Visible,
+            ..Default::default()
+        };
+
+        assert!(dm.as_byte() & 0b0000_0010 != 0);
+
+        let dm = DisplayMode {
+            cursor_visibility: Cursor::Invisible,
+            ..Default::default()
+        };
+
+        assert!(dm.as_byte() & 0b0000_0010 == 0);
+    }
+
+    #[test]
+    fn cursor_blink() {
+        let dm = DisplayMode {
+            cursor_blink: CursorBlink::On,
+            ..Default::default()
+        };
+
+        assert!(dm.as_byte() & 0b0000_0001 != 0);
+
+        let dm = DisplayMode {
+            cursor_blink: CursorBlink::Off,
+            ..Default::default()
+        };
+
+        assert!(dm.as_byte() & 0b0000_0001 == 0);
+    }
+
+    #[test]
+    fn display_visible() {
+        let dm = DisplayMode {
+            display: Display::On,
+            ..Default::default()
+        };
+
+        assert!(dm.as_byte() & 0b0000_0100 != 0);
+
+        let dm = DisplayMode {
+            display: Display::Off,
+            ..Default::default()
+        };
+
+        assert!(dm.as_byte() & 0b0000_0100 == 0);
+    }
+}