diff --git a/include/sta/assert.hpp b/include/sta/assert.hpp
index 40f5886..c695d3b 100644
--- a/include/sta/assert.hpp
+++ b/include/sta/assert.hpp
@@ -1,23 +1,51 @@
 /**
+ * @file
  * @brief Assertion handling.
- *
- * Configuration:
- *     STA_ASSERT_ENABLE:   Enable module
- *     STA_ASSERT_DISABLE:  Forces module off when defined
- *     STA_HALT:            Override function called after failed asserts
- *     DEBUG:               Automatically enables module when defined
- *     NDEBUG:              Forces module off when defined
- *
- * Both `sta::assert_failed` and `sta::assert_halt` provide weak definitions and
- * can be overridden by the application. `sta::assert_halt` is only called
- * via the **STA_HALT** macro which can also be provided by the application.
- *
- * The default implementation of `sta::assert_failed` uses **STA_DEBUG_PRINT** internally
- * and will not generate any output if the **DEBUG_SERIAL** module is disabled.
  */
 #ifndef STA_ASSERT_HPP
 #define STA_ASSERT_HPP
 
+/**
+ * @defgroup staCore Core
+ * @brief STA Core library
+ */
+
+/**
+ * @defgroup staCoreBuildConfig Build Config
+ * @ingroup staCore
+ * @brief Build configuration options
+ */
+
+/**
+ * @defgroup staCoreAssert Assert
+ * @ingroup staCore
+ * @brief Assertion handling.
+ */
+
+#ifdef DOXYGEN
+/**
+ * @def STA_ASSERT_ENABLE
+ * @brief Enable module.
+ *
+ * Automatically defined if DEBUG is defined.
+ * Automatically disabled if NDEBUG is defined.
+ *
+ * @ingroup staCoreBuildConfig
+ */
+#  define STA_ASSERT_ENABLE
+
+/**
+ * @def STA_ASSERT_DISABLE
+ * @brief Force disable module.
+ *
+ * Overrides STA_ASSERT_ENABLE option.
+ *
+ * @ingroup staCoreBuildConfig
+ */
+#  define STA_ASSERT_DISABLE
+#endif // DOXYGEN
+
+
 #include <sta/config.hpp>
 
 #ifdef DEBUG
@@ -33,6 +61,12 @@
 #endif // NDEBUG || STA_ASSERT_DISABLE
 
 
+// Show enabled module in doxygen output
+#ifdef DOXYGEN
+#  define STA_ASSERT_ENABLE
+#endif // DOXYGEN
+
+
 #ifdef STA_ASSERT_ENABLE
 
 #include <cstdint>
@@ -43,19 +77,36 @@ namespace sta
 	/**
 	 * @brief Handle failed assertions.
 	 *
+	 * The default implementation uses **STA_DEBUG_PRINT** and will not
+	 * generate any output if the **DEBUG_SERIAL** module is disabled.
+	 *
+	 * Weak implementation can be overridden.
+	 *
 	 * @param expr  Asserted expression or message
 	 * @param file  File name
 	 * @param line  Line number
+	 *
+	 * @ingroup staCoreAssert
 	 */
 	void assert_failed(const char * expr, const char * file, uint32_t line);
+
 	/**
 	 * @brief Stop execution.
+	 *
+	 * Weak implementation can be overridden.
+	 *
+	 * @ingroup staCoreAssert
 	 */
 	void assert_halt();
 } // namespace sta
 
 
-// Use assert_halt if STA_HALT is not defined
+/**
+ * @def STA_HALT
+ * @brief Set function called after failed asserts.
+ *
+ * @ingroup staCoreBuildConfig
+ */
 #  ifndef STA_HALT
 #    define STA_HALT() sta::assert_halt()
 #  endif // !STA_HALT
@@ -65,62 +116,47 @@ namespace sta
  * @brief Assert expression.
  *
  * @param expr  Expression
+ *
+ * @ingroup staCoreAssert
  */
-#  define STA_ASSERT(expr)              ((void)(!(expr) && (sta::assert_failed(#expr, __FILE__, __LINE__), 1) && (STA_HALT(), 1)))
+#  define STA_ASSERT(expr)              ( (void)( !(expr) && ( sta::assert_failed(#expr, __FILE__, __LINE__), 1 ) && ( STA_HALT(), 1 ) ) )
 /**
  * @brief Assert expression.
  *
  * @param expr  Expression
  * @param msg   Message shown on failure
+ *
+ * @ingroup staCoreAssert
  */
-#  define STA_ASSERT_MSG(expr, msg)     ((void)(!(expr) && (sta::assert_failed(msg, __FILE__, __LINE__), 1) && (STA_HALT(), 1)))
+#  define STA_ASSERT_MSG(expr, msg)     ( (void)( !(expr) && ( sta::assert_failed(msg, __FILE__, __LINE__), 1 ) && ( STA_HALT(), 1 ) ) )
 /**
  * @brief Assert expression if condition is true.
  *
  * @param cond  Condition
  * @param expr  Expression
+ *
+ * @ingroup staCoreAssert
  */
-#  define STA_ASSERT_COND(cond, expr)   ((void)((cond) ? STA_ASSERT(expr) : 1))
+#  define STA_ASSERT_COND(cond, expr)   ( (void)( (cond) ? STA_ASSERT(expr) : 1 ) )
 /**
  * @brief Assert expression if condition is true.
  *
  * @param cond  Condition
  * @param expr  Expression
  * @param msg   Message shown on failure
+ *
+ * @ingroup staCoreAssert
  */
-#  define STA_ASSERT_COND_MSG(cond, expr, msg)  ((void)((cond) ? STA_ASSERT_MSG(expr, msg)))
+#  define STA_ASSERT_COND_MSG(cond, expr, msg)  ( (void)( (cond) ? STA_ASSERT_MSG(expr, msg) ) )
 
 #else // !STA_ASSERT_ENABLE
 
-/**
- * @brief Assert expression.
- *
- * @param expr  Expression
- */
-#  define STA_ASSERT(expr, msg)         ((void)0)
-/**
- * @brief Assert expression.
- *
- * @param expr  Expression
- * @param msg   Message shown on failure
- */
-#  define STA_ASSERT_MSG(expr, msg)     ((void)0)
-/**
- * @brief Assert expression if condition is true.
- *
- * @param cond  Condition
- * @param expr  Expression
- */
-#  define STA_ASSERT_COND(cond, expr)   ((void)0)
-/**
- * @brief Assert expression if condition is true.
- *
- * @param cond  Condition
- * @param expr  Expression
- * @param msg   Message shown on failure
- */
+#  define STA_ASSERT(expr)                      ((void)0)
+#  define STA_ASSERT_MSG(expr, msg)             ((void)0)
+#  define STA_ASSERT_COND(cond, expr)           ((void)0)
 #  define STA_ASSERT_COND_MSG(cond, expr, msg)  ((void)0)
 
 #endif // !STA_ASSERT_ENABLE
 
+
 #endif // STA_ASSERT_HPP
diff --git a/include/sta/debug_serial.hpp b/include/sta/debug_serial.hpp
index c997e23..6a2b964 100644
--- a/include/sta/debug_serial.hpp
+++ b/include/sta/debug_serial.hpp
@@ -1,4 +1,5 @@
 /**
+ * @file
  * @brief Debug output via UART.
  *
  * Configuration:
@@ -15,17 +16,55 @@
 #ifndef STA_DEBUG_SERIAL_HPP
 #define STA_DEBUG_SERIAL_HPP
 
+/**
+ * @defgroup staCoreDebug Debug Serial
+ * @ingroup staCore
+ * @brief Debug serial output.
+ */
+
+#ifdef DOXYGEN
+/**
+ * @def STA_DEBUG_SERIAL_ENABLE
+ * @brief Enable module.
+ *
+ * Automatically defined if DEBUG is defined.
+ * Automatically disabled if NDEBUG is defined.
+ *
+ * @ingroup staCoreBuildConfig
+ */
+#  define STA_DEBUG_SERIAL_ENABLE
+
+/**
+ * @def STA_DEBUG_SERIAL_DISABLE
+ * @brief Force disable module.
+ *
+ * Overrides STA_DEBUG_SERIAL_ENABLE option.
+ *
+ * @ingroup staCoreBuildConfig
+ */
+#  define STA_DEBUG_SERIAL_DISABLE
+#endif // DOXYGEN
+
+
 #include <sta/config.hpp>
 
-// Check only if STA_DEBUG_SERIAL_FORCE is not defined
-#ifndef STA_DEBUG_SERIAL_FORCE
-// Disable module if NDEBUG is defined or DEBUG is not
-#  if defined(NDEBUG) || !defined(DEBUG)
-#    ifdef STA_DEBUG_SERIAL_ENABLE
-#      undef STA_DEBUG_SERIAL_ENABLE
-#    endif // STA_DEBUG_SERIAL_ENABLE
-#  endif // NDEBUG || !DEBUG
-#endif // !STA_DEBUG_SERIAL_FORCE
+#ifdef DEBUG
+#  ifndef STA_DEBUG_SERIAL_ENABLE
+#    define STA_DEBUG_SERIAL_ENABLE
+#  endif // !STA_DEBUG_SERIAL_ENABLE
+#endif // DEBUG
+
+#if defined(NDEBUG) || defined(STA_DEBUG_SERIAL_DISABLE)
+#  ifdef STA_DEBUG_SERIAL_ENABLE
+#    undef STA_DEBUG_SERIAL_ENABLE
+#  endif // STA_DEBUG_SERIAL_ENABLE
+#endif // NDEBUG || STA_DEBUG_SERIAL_DISABLE
+
+
+// Show enabled module in doxygen output
+#ifdef DOXYGEN
+#  define STA_DEBUG_SERIAL_ENABLE
+#endif // DOXYGEN
 
 
 #ifdef STA_DEBUG_SERIAL_ENABLE
@@ -35,15 +74,35 @@
 
 namespace sta
 {
+	/**
+	 * @brief %UART print object for debug serial output.
+	 *
+	 * @ingroup staCoreDebug
+	 */
 	extern PrintableUART DebugSerial;
 } // namespace sta
 
 
+/**
+ * @brief Print debug output to UART.
+ *
+ * @param ... See @ref sta::PrintableUART::print
+ *
+ * @ingroup staCoreDebug
+ */
 #  define STA_DEBUG_PRINT(...)      sta::DebugSerial.print(__VA_ARGS__)
+/**
+ * @brief Print debug output followed by new-line to UART.
+ *
+ * @param ... See @ref sta::PrintableUART::println
+ *
+ * @ingroup staCoreDebug
+ */
 #  define STA_DEBUG_PRINTLN(...)    sta::DebugSerial.println(__VA_ARGS__)
 #else // !STA_DEBUG_SERIAL_ENABLE
 #  define STA_DEBUG_PRINT(...)      ((void)0)
 #  define STA_DEBUG_PRINTLN(...)    ((void)0)
 #endif // !STA_DEBUG_SERIAL_ENABLE
 
+
 #endif // STA_DEBUG_SERIAL_HPP
diff --git a/include/sta/endian.hpp b/include/sta/endian.hpp
index cdec661..41abaa2 100644
--- a/include/sta/endian.hpp
+++ b/include/sta/endian.hpp
@@ -1,9 +1,16 @@
 /**
+ * @file
  * @brief Helper macros for managing endian handling.
  */
 #ifndef STA_ENDIAN_HPP
 #define STA_ENDIAN_HPP
 
+/**
+ * @defgroup staCoreEndian Endian
+ * @ingroup staCore
+ * @brief Endian handling.
+ */
+
 #include <sta/config.hpp>
 
 #if !defined(STA_MCU_BIG_ENDIAN) && !defined(STA_MCU_LITTLE_ENDIAN)
@@ -16,6 +23,8 @@
  *
  * @param u16   16-bit input value
  * @return      16-bit value w/ swapped byte order
+ *
+ * @ingroup staCoreEndian
  */
 #define STA_UINT16_SWAP_BYTE_ORDER(u16) \
 	( \
@@ -28,6 +37,8 @@
  *
  * @param u32   32-bit input value
  * @return      32-bit value w/ swapped byte order
+ *
+ * @ingroup staCoreEndian
  */
 #define STA_UINT32_SWAP_BYTE_ORDER(u32) \
 	( \
@@ -42,6 +53,8 @@
  *
  * @param u16   16-bit input value
  * @return      Initializer list for uint8_t[2]
+ *
+ * @ingroup staCoreEndian
  */
 #define STA_UINT16_TO_BYTES_BE(u16) \
 	{ \
@@ -54,6 +67,8 @@
  *
  * @param u16   16-bit input value
  * @return      Initializer list for uint8_t[2]
+ *
+ * @ingroup staCoreEndian
  */
 #define STA_UINT16_TO_BYTES_LE(u16) \
 	{ \
@@ -66,6 +81,8 @@
  *
  * @param u32   32-bit input value
  * @return      Initializer list for uint8_t[4]
+ *
+ * @ingroup staCoreEndian
  */
 #define STA_UINT32_TO_BYTES_BE(u32) \
 	{ \
@@ -80,6 +97,8 @@
  *
  * @param u32   32-bit input value
  * @return      Initializer list for uint8_t[4]
+ *
+ * @ingroup staCoreEndian
  */
 #define STA_UINT32_TO_BYTES_LE(u32) \
 	{ \
@@ -90,132 +109,95 @@
 	}
 
 
+/**
+ * @defe STA_UINT16_TO_BE(u16)
+ * @brief Convert 16-bit value to big-endian byte order.
+ *
+ * @param u16   16-bit input value
+ * @return      16-bit value w/ big-endian byte order
+ */
+
+/**
+ * @def STA_UINT16_TO_LE(u16)
+ * @brief Convert 16-bit value to little-endian byte order.
+ *
+ * @param u16   16-bit input value
+ * @return      16-bit value w/ little-endian byte order
+ */
+
+/**
+ * @def STA_UINT16_TO_BYTES(u16)
+ * @brief Get initializer list for byte array w/ MCU byte order from 16-bit value.
+ *
+ * @param u16   16-bit input value
+ * @return      Initializer list for uint8_t[2]
+ */
+
+/**
+ * @def STA_UINT16_TO_BYTES_SWAP(u16)
+ * @brief Get initializer list for byte array w/ swapped MCU byte order from 16-bit value.
+ *
+ * @param u16   16-bit input value
+ * @return      Initializer list for uint8_t[2]
+ */
+
+/**
+ * @def STA_UINT32_TO_BE(u32)
+ * @brief Convert 32-bit value to big-endian byte order.
+ *
+ * @param u32   32-bit input value
+ * @return      32-bit value w/ big-endian byte order
+ */
+
+/**
+ * @def STA_UINT32_TO_LE(u32)
+ * @brief Convert 32-bit value to little-endian byte order.
+ *
+ * @param u32   32-bit input value
+ * @return      32-bit value w/ little-endian byte order
+ */
+
+/**
+ * @def STA_UINT32_TO_BYTES(u32)
+ * @brief Get initializer list for byte array from 32-bit value.
+ *
+ * @param u32   32-bit input value
+ * @return      Initializer list for uint8_t[4]
+ */
+
+/**
+ * @def STA_UINT32_TO_BYTES_SWAP(u32)
+ * @brief Get initializer list for byte array w/ swapped byte order from 32-bit value.
+ *
+ * @param u32   32-bit input value
+ * @return      Initializer list for uint8_t[4]
+ */
+
 
 #ifdef STA_MCU_LITTLE_ENDIAN
 
-
-/**
- * @brief Convert 16-bit value to big-endian byte order.
- *
- * @param u16   16-bit input value
- * @return      16-bit value w/ big-endian byte order
- */
 #  define STA_UINT16_TO_BE(u16)             STA_UINT16_SWAP_BYTE_ORDER(u16)
-/**
- * @brief Convert 16-bit value to little-endian byte order.
- *
- * @param u16   16-bit input value
- * @return      16-bit value w/ little-endian byte order
- */
 #  define STA_UINT16_TO_LE(u16)             (u16)
-/**
- * @brief Get initializer list for byte array w/ MCU byte order from 16-bit value.
- *
- * @param u16   16-bit input value
- * @return      Initializer list for uint8_t[2]
- */
 #  define STA_UINT16_TO_BYTES(u16)          STA_UINT16_TO_BYTES_LE(u16)
-/**
- * @brief Get initializer list for byte array w/ swapped MCU byte order from 16-bit value.
- *
- * @param u16   16-bit input value
- * @return      Initializer list for uint8_t[2]
- */
-#  define STA_UINT16_TO_BYTES_SWAP(u16)  STA_UINT16_TO_BYTES_BE(u16)
+#  define STA_UINT16_TO_BYTES_SWAP(u16)     STA_UINT16_TO_BYTES_BE(u16)
 
-/**
- * @brief Convert 32-bit value to big-endian byte order.
- *
- * @param u32   32-bit input value
- * @return      32-bit value w/ big-endian byte order
- */
 #  define STA_UINT32_TO_BE(u32)             STA_UINT32_SWAP_BYTE_ORDER(u32)
-/**
- * @brief Convert 32-bit value to little-endian byte order.
- *
- * @param u32   32-bit input value
- * @return      32-bit value w/ little-endian byte order
- */
 #  define STA_UINT32_TO_LE(u32)             (u32)
-/**
- * @brief Get initializer list for byte array from 32-bit value.
- *
- * @param u32   32-bit input value
- * @return      Initializer list for uint8_t[4]
- */
 #  define STA_UINT32_TO_BYTES(u32)          STA_UINT32_TO_BYTES_LE(u32)
-/**
- * @brief Get initializer list for byte array w/ swapped byte order from 32-bit value.
- *
- * @param u32   32-bit input value
- * @return      Initializer list for uint8_t[4]
- */
 #  define STA_UINT32_TO_BYTES_SWAP(u32)     STA_UINT32_TO_BYTES_BE(u32)
 
-
 #elif STA_MCU_BIG_ENDIAN
 
-
-/**
- * @brief Convert 16-bit value to big-endian byte order.
- *
- * @param u16   16-bit input value
- * @return      16-bit value w/ big-endian byte order
- */
 #  define STA_UINT16_TO_BE(u16)             (u16)
-/**
- * @brief Convert 16-bit value to little-endian byte order.
- *
- * @param u16   16-bit input value
- * @return      16-bit value w/ little-endian byte order
- */
 #  define STA_UINT16_TO_LE(u16)             STA_UINT16_SWAP_BYTE_ORDER(u16)
-/**
- * @brief Get initializer list for byte array w/ MCU byte order from 16-bit value.
- *
- * @param u16   16-bit input value
- * @return      Initializer list for uint8_t[2]
- */
 #  define STA_UINT16_TO_BYTES(u16)          STA_UINT16_TO_BYTES_BE(u16)
-/**
- * @brief Get initializer list for byte array w/ swapped MCU byte order from 16-bit value.
- *
- * @param u16   16-bit input value
- * @return      Initializer list for uint8_t[2]
- */
 #  define STA_UINT16_TO_BYTES_SWAP(u16)     STA_UINT16_TO_BYTES_LE(u16)
 
-
-/**
- * @brief Convert 32-bit value to big-endian byte order.
- *
- * @param u32   32-bit input value
- * @return      32-bit value w/ big-endian byte order
- */
 #  define STA_UINT32_TO_BE(u32)             (u32)
-/**
- * @brief Convert 32-bit value to little-endian byte order.
- *
- * @param u32   32-bit input value
- * @return      32-bit value w/ little-endian byte order
- */
 #  define STA_UINT32_TO_LE(u32)             STA_UINT32_SWAP_BYTE_ORDER(u32)
-/**
- * @brief Get initializer list for byte array from 32-bit value.
- *
- * @param u32   32-bit input value
- * @return      Initializer list for uint8_t[4]
- */
 #  define STA_UINT32_TO_BYTES(u32)          STA_UINT32_TO_BYTES_BE(u32)
-/**
- * @brief Get initializer list for byte array w/ swapped byte order from 32-bit value.
- *
- * @param u32   32-bit input value
- * @return      Initializer list for uint8_t[4]
- */
 #  define STA_UINT32_TO_BYTES_SWAP(u32)     STA_UINT32_TO_BYTES_LE(u32)
 
-
 #endif // STA_MCU_BIG_ENDIAN
 
 
diff --git a/include/sta/enum_flags.hpp b/include/sta/enum_flags.hpp
index c480698..f848487 100644
--- a/include/sta/enum_flags.hpp
+++ b/include/sta/enum_flags.hpp
@@ -1,4 +1,5 @@
 /**
+ * @file
  * @brief Helper for using enum values as flags.
  */
 #ifndef STA_ENUM_FLAGS_HPP
@@ -13,6 +14,8 @@ namespace sta
 	 * @brief 32-bit flag register with enum type representing single flag bits.
 	 *
 	 * @tparam F    Enum type used for flag bits
+	 *
+	 * @ingroup staCore
 	 */
 	template <typename F>
 	class EnumFlags
@@ -151,6 +154,8 @@ namespace sta
  * @brief Provide overload for operator | to combine enum values.
  *
  * @param enumType  Enum type to overload
+ *
+ * @ingroup staCore
  */
 #define STA_ENUM_FLAGS_OVERLOAD(enumType) \
 	sta::EnumFlags<enumType> operator |(enumType lhs, enumType rhs) \
@@ -162,6 +167,8 @@ namespace sta
  * @brief Declare alias for sta::EnumFlags specialization.
  *
  * @param enumType  Enum type for specialization
+ *
+ * @ingroup staCore
  */
 #define STA_ENUM_FLAGS_ALIAS(enumType) \
 	using enumType ## Flags = sta::EnumFlags<enumType>
@@ -172,6 +179,8 @@ namespace sta
  * @param enumType  Name of new enum class
  * @param value1    First enum value
  * @param ...       Enum values 2 - 32
+ *
+ * @ingroup staCore
  */
 #define STA_ENUM_FLAGS_DECL(enumType, value1, ...) \
 	enum class enumType \
diff --git a/include/sta/fifo_buffer.hpp b/include/sta/fifo_buffer.hpp
index e9fc768..2971712 100644
--- a/include/sta/fifo_buffer.hpp
+++ b/include/sta/fifo_buffer.hpp
@@ -1,3 +1,7 @@
+/**
+ * @file
+ * @brief FIFO buffer type.
+ */
 #ifndef STA_FIFO_BUFFER_HPP
 #define STA_FIFO_BUFFER_HPP
 
@@ -9,6 +13,8 @@ namespace sta
 	 *
 	 * @tparam Size     Size type
 	 * @tparam N        Buffer size
+	 *
+	 * @ingroup staCore
 	 */
 	template <typename Size, Size N>
 	class FifoBuffer
diff --git a/include/sta/lang.hpp b/include/sta/lang.hpp
index 02b8046..a09b2ba 100644
--- a/include/sta/lang.hpp
+++ b/include/sta/lang.hpp
@@ -1,34 +1,66 @@
 /**
+ * @file
  * @brief Helper for useful compiler features.
  */
 #ifndef STA_LANG_HPP
 #define STA_LANG_HPP
 
+/**
+ * @defgroup staCoreLang Lang
+ * @ingroup staCore
+ * @brief Compiler instructions.
+ * @{
+ */
 
+
+/**
+ * @brief Assembler instruction.
+ */
 #ifndef STA_ASM
 #  define STA_ASM 			__asm
 #endif // STA_ASM
 
+/**
+ * @brief Mark as deprecated.
+ */
 #ifndef STA_DEPRECATED
 #  define STA_DEPRECATED	__attribute__((deprecated))
 #endif // STA_DEPRECATED
 
+/**
+ * @brief Mark as weak definition.
+ */
 #ifndef STA_WEAK
 #  define STA_WEAK 			__attribute__((weak))
 #endif // STA_WEAK
 
+
+/**
+ * @brief Mark as field w/o added padding.
+ */
 #ifndef STA_PACKED
 #  define STA_PACKED		__attribute__((packed))
 #endif // STA_PACKED
 
+/**
+ * @brief Mark as struct w/o added padding.
+ */
 #ifndef STA_PACKED_STRUCT
 #  define STA_PACKED_STRUCT	struct STA_PACKED
 #endif // STA_PACKED_STRUCT
 
+/**
+ * @brief Mark as union w/o added padding.
+ */
 #ifndef STA_PACKED_UNION
 #  define STA_PACKED_UNION	union STA_PACKED
 #endif // STA_PACKED_UNION
 
+/**
+ * @brief Add breakpoint.
+ *
+ * @param value Additional uint16_t data for debugger
+ */
 #ifndef STA_BKPT
 #  define STA_BKPT(value)	STA_ASM volatile ("bkpt "#value)
 #endif // STA_BKPT
@@ -37,17 +69,48 @@
 // TODO Check for GCC
 
 /**
- * @brief Helper for silencing compiler warnings in unreachable code locations.
+ * @brief Silencing compiler warnings in unreachable code locations.
  *
- * Example: Default of switch handling all cases of enum class
+ * Example:
+ * @code
+ * enum class E { A };
+ *
+ * E val = A;
+ *
+ * switch (val)
+ * {
+ * case E::A:
+ *     break;
+ *
+ * default:
+ *     // All enum values already handled
+ *     STA_UNREACHABLE();
+ * }
+ * @endcode
  */
 #ifndef STA_UNREACHABLE
 #  define STA_UNREACHABLE() __builtin_unreachable()
 #endif // !STA_UNREACHABLE
 
+/**
+ * @brief Silencing compiler warnings for intended switch case fallthrough.
+ *
+ * Example:
+ * @code
+ * switch (val)
+ * {
+ * case A: STA_FALLTHROUGH();
+ * case B:
+ *     do();
+ *     break;
+ * }
+ * @endcode
+ */
 #ifndef STA_FALLTRHOUGH
 #  define STA_FALLTHROUGH() __attribute__((fallthrough))
 #endif // !STA_FALLTRHOUGH
 
 
+/** @} */
+
 #endif // STA_LANG_HPP
diff --git a/include/sta/printable_uart.hpp b/include/sta/printable_uart.hpp
index 38c2912..35e62eb 100644
--- a/include/sta/printable_uart.hpp
+++ b/include/sta/printable_uart.hpp
@@ -15,6 +15,8 @@ namespace sta
 {
 	/**
 	 * @brief Integer representation.
+	 *
+	 * @ingroup staCore
 	 */
 	enum class IntegerBase
 	{
@@ -25,6 +27,8 @@ namespace sta
 
 	/**
 	 * @brief Printable interface for UART.
+	 *
+	 * @ingroup staCore
 	 */
 	class PrintableUART
 	{
diff --git a/include/sta/printf.hpp b/include/sta/printf.hpp
index 7074460..a48de80 100644
--- a/include/sta/printf.hpp
+++ b/include/sta/printf.hpp
@@ -1,9 +1,29 @@
 /**
- * @brief Compatibility layer for different `printf` implementations.
+ * @file
+ * @brief Compatibility layer for different printf implementations.
  */
 #ifndef STA_PRINTF_HPP
 #define STA_PRINTF_HPP
 
+#ifdef DOXYGEN
+/**
+ * @def STA_PRINTF_USE_STDLIB
+ * @brief Use printf implementation from STD library.
+ *
+ * @ingroup staCoreBuildConfig
+ */
+#  define STA_PRINTF_USE_STDLIB
+
+/**
+ * @def STA_PRINTF_USE_MPALAND
+ * @brief Use printf implementation from Marco Paland.
+ *
+ * @ingroup staCoreBuildConfig
+ */
+#  define STA_PRINTF_USE_MPALAND
+#endif // DOXYGEN
+
+
 #include <sta/config.hpp>
 
 #if !defined(STA_PRINTF_USE_STDLIB) && !defined(STA_PRINTF_USE_MPALAND)