diff --git a/include/etl/intrusive_timer.h b/include/etl/intrusive_timer.h
index 2a7cae1a..4a3d7516 100644
--- a/include/etl/intrusive_timer.h
+++ b/include/etl/intrusive_timer.h
@@ -157,7 +157,7 @@ namespace etl
     // Returns true if the tick was processed,
     // false if not.
     //*******************************************
-    bool tick(uint32_t count)
+    bool tick(etl::timer::interval::type count)
     {
       bool was_processed = false;
 
@@ -286,7 +286,7 @@ namespace etl
     //*******************************************
     /// Sets a timer's interval.
     //*******************************************
-    bool set_interval(etl::timer::node& timer_, uint32_t interval_) ETL_NOEXCEPT
+    bool set_interval(etl::timer::node& timer_, etl::timer::interval::type interval_) ETL_NOEXCEPT
     {
       bool result = false;
 
@@ -389,9 +389,9 @@ namespace etl
     /// Returns etl::timer::interval::No_Interval if there is no active
     /// timer.
     //*******************************************
-    uint32_t time_to_next() const ETL_NOEXCEPT
+    etl::timer::interval::type time_to_next() const ETL_NOEXCEPT
     {
-      uint32_t delta = static_cast<uint32_t>(etl::timer::interval::No_Interval);
+      etl::timer::interval::type delta = static_cast<etl::timer::interval::type>(etl::timer::interval::No_Interval);
 
       lock_policy.lock();
 
diff --git a/include/etl/timer.h b/include/etl/timer.h
index 503f7691..da950ba2 100644
--- a/include/etl/timer.h
+++ b/include/etl/timer.h
@@ -31,6 +31,7 @@ SOFTWARE.
 
 #include "platform.h"
 #include "atomic.h"
+#include "limits.h"
 
 #include <stdint.h>
 
@@ -48,10 +49,10 @@ namespace etl
   #endif
 #endif
 
-  //***************************************************************************
-  /// Common definitions for the timer framework.
-  //***************************************************************************
-  namespace timer
+    //***************************************************************************
+    /// Common definitions for the timer framework.
+    //***************************************************************************
+    namespace timer
   {
     // Timer modes.
     struct mode
@@ -87,41 +88,45 @@ namespace etl
     // Timer id.
     struct id
     {
+      typedef uint_least8_t type;
+
       enum
       {
-        NO_TIMER = 255, // Deprecated
-        No_Timer = 255
+        NO_TIMER = etl::integral_limits<type>::max, // Deprecated
+        No_Timer = etl::integral_limits<type>::max
       };
-
-      typedef uint_least8_t type;
     };
 
     // Timer state.
     struct state
     {
+      typedef uint32_t type;
+
       enum
       {
-        INACTIVE = 0xFFFFFFFFUL, // Deprecated
-        Inactive = 0xFFFFFFFFUL
+        INACTIVE = etl::integral_limits<type>::max, // Deprecated
+        Inactive = etl::integral_limits<type>::max
       };
     };
 
     // Timer time interval.
     struct interval
     {
+      typedef uint32_t type;
+
       enum
       {
-        No_Active_Interval = 0xFFFFFFFFUL, // Deprecated
-        No_Interval        = 0xFFFFFFFFUL
+        No_Active_Interval = etl::integral_limits<type>::max, // Deprecated
+        No_Interval        = etl::integral_limits<type>::max
       };
-
-      typedef uint32_t type;
     };
 
     // Timer owner.
     struct owner
     {
-      static ETL_CONSTANT void* No_Owner = ETL_NULLPTR;
+      typedef void* type;
+
+      static ETL_CONSTANT type No_Owner = ETL_NULLPTR;
     };
   } // namespace timer
 } // namespace etl
diff --git a/include/etl/timer_config.h b/include/etl/timer_config.h
index 448dc0da..00b3073b 100644
--- a/include/etl/timer_config.h
+++ b/include/etl/timer_config.h
@@ -89,7 +89,7 @@ namespace etl
       //*******************************************
       /// Constructor.
       //*******************************************
-      ETL_CONSTEXPR config(uint32_t interval_, etl::timer::mode::type mode_) ETL_NOEXCEPT
+      ETL_CONSTEXPR config(etl::timer::interval::type interval_, etl::timer::mode::type mode_) ETL_NOEXCEPT
         : interval(interval_)
         , mode(mode_)
         , id(etl::timer::id::No_Timer)
@@ -99,7 +99,7 @@ namespace etl
       //*******************************************
       /// Returns the interval of the timer.
       //*******************************************
-      ETL_CONSTEXPR uint32_t get_interval() const ETL_NOEXCEPT
+      ETL_CONSTEXPR etl::timer::interval::type get_interval() const ETL_NOEXCEPT
       {
         return interval;
       }
@@ -132,9 +132,9 @@ namespace etl
 
     private:
 
-      uint32_t               interval; ///< The interval of the timer.
-      etl::timer::mode::type mode;     ///< Whether the timer is repeating or single-shot.
-      etl::timer::id::type   id;       ///< The id of the timer.
+      etl::timer::interval::type interval; ///< The interval of the timer.
+      etl::timer::mode::type     mode;     ///< Whether the timer is repeating or single-shot.
+      etl::timer::id::type       id;       ///< The id of the timer.
     };
   } // namespace timer
 } // namespace etl
diff --git a/include/etl/timer_node.h b/include/etl/timer_node.h
index b0c60a43..cb37a1e9 100644
--- a/include/etl/timer_node.h
+++ b/include/etl/timer_node.h
@@ -134,7 +134,7 @@ namespace etl
       //*******************************************
       /// Returns the delta of the timer.
       //*******************************************
-      ETL_CONSTEXPR uint32_t get_delta() const ETL_NOEXCEPT
+      ETL_CONSTEXPR etl::timer::interval::type get_delta() const ETL_NOEXCEPT
       {
         return delta;
       }
@@ -142,7 +142,7 @@ namespace etl
       //*******************************************
       /// Returns the interval of the timer.
       //*******************************************
-      ETL_CONSTEXPR uint32_t get_interval() const ETL_NOEXCEPT
+      ETL_CONSTEXPR etl::timer::interval::type get_interval() const ETL_NOEXCEPT
       {
         return config.get_interval();
       }
@@ -192,7 +192,7 @@ namespace etl
       //*******************************************
       /// Sets the interval of the timer.
       //*******************************************
-      void set_interval(uint32_t interval_) ETL_NOEXCEPT
+      void set_interval(etl::timer::interval::type interval_) ETL_NOEXCEPT
       {
         config.interval = interval_;
       }
@@ -284,12 +284,12 @@ namespace etl
 
       node& operator=(const node&) ETL_DELETE;
 
-      node*    registered_next; ///< The next timer in the registered timer list. unlinked() if the timer is not registered.
-      node*    active_next;     ///< The next timer in the active timer list. unlinked() if the timer is not active.
-      node*    expired_next;    ///< The next timer in the expired timer list. unlinked() if the timer is not expired.
-      void*    owner;           ///< The owner of the timer.
-      config   config;          ///< The configuration of the timer.
-      uint32_t delta;           ///< The time remaining until the timer expires.
+      node*                      registered_next; ///< The next timer in the registered timer list. unlinked() if the timer is not registered.
+      node*                      active_next;     ///< The next timer in the active timer list. unlinked() if the timer is not active.
+      node*                      expired_next;    ///< The next timer in the expired timer list. unlinked() if the timer is not expired.
+      void*                      owner;           ///< The owner of the timer.
+      config                     config;          ///< The configuration of the timer.
+      etl::timer::interval::type delta;           ///< The time remaining until the timer expires.
     };
 
     //***************************************************************************