diff --git a/eink.hpp b/eink.hpp
index 418ce91..ce1ca0b 100644
--- a/eink.hpp
+++ b/eink.hpp
@@ -12,21 +12,21 @@ namespace eink {
 
 template <uint16_t Width, uint16_t Height, typename Spi, io::P RstPin, io::P DcPin, io::P BusyPin>
 class Eink {
-	struct Cmd {
-		static constexpr auto SW_RESET = uint8_t{0x12};
-		static constexpr auto DRIVER_OUTPUT_CONTROL = uint8_t{0x01};
-		static constexpr auto DATA_ENTRY_MODE = uint8_t{0x11};
-		static constexpr auto SET_RAM_X_ADDR_POSITIONS = uint8_t{0x44};
-		static constexpr auto SET_RAM_Y_ADDR_POSITIONS = uint8_t{0x45};
-		static constexpr auto BORDER_WAVEFORM_CONTROL = uint8_t{0x3C};
-		static constexpr auto READ_TEMPERATURE_SENSOR = uint8_t{0x18};
-		static constexpr auto SET_RAM_X_ADDR = uint8_t{0x4E};
-		static constexpr auto SET_RAM_Y_ADDR = uint8_t{0x4F};
-		static constexpr auto WRITE_RAM_BLACK = uint8_t{0x24};
-		static constexpr auto WRITE_RAM_RED = uint8_t{0x26};
-		static constexpr auto DISPLAY_UPDATE_CONTROL_2 = uint8_t{0x22};
-		static constexpr auto UPDATE_DISPLAY = uint8_t{0x20};
-		static constexpr auto DEEP_SLEEP_MODE = uint8_t{0x10};
+	enum class Cmd : uint8_t {
+		DRIVER_OUTPUT_CONTROL = 0x01,
+		DEEP_SLEEP_MODE = 0x10,
+		DATA_ENTRY_MODE = 0x11,
+		SW_RESET = 0x12,
+		READ_TEMPERATURE_SENSOR = 0x18,
+		UPDATE_DISPLAY = 0x20,
+		DISPLAY_UPDATE_CONTROL_2 = 0x22,
+		WRITE_RAM_BLACK = 0x24,
+		WRITE_RAM_RED = 0x26,
+		BORDER_WAVEFORM_CONTROL = 0x3C,
+		SET_RAM_X_ADDR_POSITIONS = 0x44,
+		SET_RAM_Y_ADDR_POSITIONS = 0x45,
+		SET_RAM_X_ADDR = 0x4E,
+		SET_RAM_Y_ADDR = 0x4F,
 	};
 
 	static io::Pin<RstPin> m_rst;
@@ -106,10 +106,10 @@ class Eink {
 		waitUntilIdle();
 	}
 
-	static void sendCommand(const uint8_t command)
+	static void sendCommand(const Cmd command)
 	{
 		m_dc = false;
-		spiTransfer(command);
+		spiTransfer(static_cast<uint8_t>(command));
 	}
 
 	static void sendData(const uint8_t data)