diff --git a/third-party/TeensyTimerTool/examples/01_Basic/HelloPeriodic/HelloPeriodic.ino b/third-party/TeensyTimerTool/examples/01_Basic/HelloPeriodic/HelloPeriodic.ino
index 391db61..e4ecc97 100644
--- a/third-party/TeensyTimerTool/examples/01_Basic/HelloPeriodic/HelloPeriodic.ino
+++ b/third-party/TeensyTimerTool/examples/01_Basic/HelloPeriodic/HelloPeriodic.ino
@@ -1,10 +1,10 @@
 /********************************************************
  * Basic usage of the timer
- * 
+ *
  * Generates a timer from the timer pool and
- * starts it with a period of 250ms. 
+ * starts it with a period of 250ms.
  * The timer callback simply toggles the built in LED
- * 
+ *
  ********************************************************/
 
 #include "TeensyTimerTool.h"
@@ -13,17 +13,17 @@ using namespace TeensyTimerTool;
 
 void callback()
 {
-    digitalWriteFast(LED_BUILTIN, !digitalReadFast(LED_BUILTIN));    
+    digitalWriteFast(LED_BUILTIN, !digitalReadFast(LED_BUILTIN));
 }
 
-Timer t1; // generate a timer from the pool (Pool: 2xGPT, 16xTMR(QUAD), 20xTCK)
+PeriodicTimer t1; // generate a timer from the pool (Pool: 2xGPT, 16xTMR(QUAD), 20xTCK)
 
 void setup()
 {
-    pinMode(LED_BUILTIN,OUTPUT);   
-    t1.beginPeriodic(callback, 250'000); // 250ms       
+    pinMode(LED_BUILTIN,OUTPUT);
+    t1.begin(callback, 250'000); // 250ms
 }
 
 void loop()
-{   
+{
 }
diff --git a/third-party/TeensyTimerTool/examples/01_Basic/MoreTimers/MoreTimers.ino b/third-party/TeensyTimerTool/examples/01_Basic/MoreTimers/MoreTimers.ino
index 2506585..fba91cb 100644
--- a/third-party/TeensyTimerTool/examples/01_Basic/MoreTimers/MoreTimers.ino
+++ b/third-party/TeensyTimerTool/examples/01_Basic/MoreTimers/MoreTimers.ino
@@ -1,11 +1,15 @@
+//-----------------------
+// REQUIRES T4.x
+//-----------------------
+
 #include "TeensyTimerTool.h"
 
 using namespace TeensyTimerTool;
 
-Timer t1(TCK);  // Tick-Timer does not use any hardware timer (20 32bit channels)
-Timer t2(TMR1); // First channel on TMR1 aka QUAD timer module. (TMR1 - TMR4, four 16bit channels each)
-Timer t3(GPT1); // GPT1 module (one 32bit channel per module)
-Timer t4(TMR1); // Second channel on TMR1
+PeriodicTimer t1(TCK);  // Tick-Timer does not use any hardware timer (20 32bit channels)
+PeriodicTimer t2(TMR1); // First channel on TMR1 aka QUAD timer module. (TMR1 - TMR4, four 16bit channels each)
+PeriodicTimer t3(GPT1); // GPT1 module (one 32bit channel per module)
+OneShotTimer t4(TMR1);  // Second channel on TMR1
 
 // Callbacks ===================================================================================
 
@@ -38,15 +42,14 @@ void LED_OFF()
 
 void setup()
 {
-    for(unsigned pin = 0; pin <=13; pin++) pinMode(pin,OUTPUT);    
+    for (unsigned pin = 0; pin <= 13; pin++) pinMode(pin, OUTPUT);
 
-    t1.beginPeriodic(pulse200ns,   50'000); // 200ns pulse every 500 ms
-    t2.beginPeriodic(pulse400ns,      100); // 400ns pulse every 100 µs  
-    t3.beginPeriodic(LED_ON,    1'000'000); // Switch LED on every second
-    t4.beginOneShot(LED_OFF);               // One shot timer to switch LED Off
+    t1.begin(pulse200ns, 50'000); // 200ns pulse every 500 ms
+    t2.begin(pulse400ns, 100);    // 400ns pulse every 100 µs
+    t3.begin(LED_ON, 1'000'000);  // Switch LED on every second
+    t4.begin(LED_OFF);            // One shot timer to switch LED Off
 }
 
 void loop()
-{   
+{
 }
-
diff --git a/third-party/TeensyTimerTool/examples/01_Basic/UsingChronoDurations1/UsingChronoDurations1.ino b/third-party/TeensyTimerTool/examples/01_Basic/UsingChronoDurations1/UsingChronoDurations1.ino
index 44173d2..fb33295 100644
--- a/third-party/TeensyTimerTool/examples/01_Basic/UsingChronoDurations1/UsingChronoDurations1.ino
+++ b/third-party/TeensyTimerTool/examples/01_Basic/UsingChronoDurations1/UsingChronoDurations1.ino
@@ -27,7 +27,6 @@ void setup()
 
     t1.begin(isr1, 5.02s);   // instead of 5020000 (µs)
     t2.begin(isr2, 25ms);    // instead of   25000 (µs)
-    t2.begin(isr3, 100_kHz); // instead of      10 (µs)
 }
 
 void loop()
diff --git a/third-party/TeensyTimerTool/examples/01_Basic/UsingChronoDurations2/UsingChronoDurations2.ino b/third-party/TeensyTimerTool/examples/01_Basic/UsingChronoDurations2/UsingChronoDurations2.ino
index db54e9b..401c0da 100644
--- a/third-party/TeensyTimerTool/examples/01_Basic/UsingChronoDurations2/UsingChronoDurations2.ino
+++ b/third-party/TeensyTimerTool/examples/01_Basic/UsingChronoDurations2/UsingChronoDurations2.ino
@@ -25,7 +25,7 @@ void setup()
     timer[3].trigger(milliseconds(50) + microseconds(5000)); // 55ms
     t_0 = millis();
 
-    pt1.begin([]{digitalToggleFast(LED_BUILTIN)})
+    pt1.begin([] { digitalToggleFast(LED_BUILTIN); }, 0.5s);
 }
 
 void loop()
diff --git a/third-party/TeensyTimerTool/examples/02_Advanced/CallbackWithParams/CallbackWithParams.ino b/third-party/TeensyTimerTool/examples/02_Advanced/CallbackWithParams/CallbackWithParams.ino
index 4f1dc95..c359b35 100644
--- a/third-party/TeensyTimerTool/examples/02_Advanced/CallbackWithParams/CallbackWithParams.ino
+++ b/third-party/TeensyTimerTool/examples/02_Advanced/CallbackWithParams/CallbackWithParams.ino
@@ -4,7 +4,7 @@ using namespace TeensyTimerTool;
 
 void callback(int& someInt, int cnt)  // this callback has context, i.e. parameter
 {
-    for (int i = 0; i < cnt; i++)     // whenn called, print out someInt cnt times
+    for (int i = 0; i < cnt; i++)     // when called, print out someInt cnt times
     {
         Serial.print(someInt);
         Serial.print(" | ");
@@ -14,12 +14,12 @@ void callback(int& someInt, int cnt)  // this callback has context, i.e. paramet
 
 //==============================================================
 
-Timer t;
+PeriodicTimer t;
 int number = 0;
 
 void setup()
 {
-    t.beginPeriodic([] { callback(number, 5); }, 50'000);
+    t.begin([] { callback(number, 5); }, 50ms);
 }
 
 void loop()
diff --git a/third-party/TeensyTimerTool/examples/02_Advanced/UsingLambdas/UsingLambdas.ino b/third-party/TeensyTimerTool/examples/02_Advanced/UsingLambdas/UsingLambdas.ino
index 62c71b7..94becfc 100644
--- a/third-party/TeensyTimerTool/examples/02_Advanced/UsingLambdas/UsingLambdas.ino
+++ b/third-party/TeensyTimerTool/examples/02_Advanced/UsingLambdas/UsingLambdas.ino
@@ -6,11 +6,11 @@ using namespace TeensyTimerTool;
 using namespace pins;
 
 pin<13> LED(OUTPUT);
-Timer timer;
+OneShotTimer timer;
 
 void setup()
 {
-    timer.beginOneShot([] { LED = LOW; });
+    timer.begin([] { LED = LOW; });
 }
 
 void loop()
diff --git a/third-party/TeensyTimerTool/examples/03_Applications/DoubleExposure/DoubleExposure.ino b/third-party/TeensyTimerTool/examples/03_Applications/DoubleExposure/DoubleExposure.ino
index f50866b..d3e3a48 100644
--- a/third-party/TeensyTimerTool/examples/03_Applications/DoubleExposure/DoubleExposure.ino
+++ b/third-party/TeensyTimerTool/examples/03_Applications/DoubleExposure/DoubleExposure.ino
@@ -1,12 +1,12 @@
-#include "ResponsiveAnalogRead.h"
 #include "SystemController.h"
 
-constexpr unsigned potPin = A0;
-ResponsiveAnalogRead pot(potPin, false);
+// --> Uncomment if you have a control voltage on the pot pin  <--
+// #include "ResponsiveAnalogRead.h"
+// constexpr unsigned potPin = A0;
+// ResponsiveAnalogRead pot(potPin, false);
 
 SystemController sysControl;
 
-
 void setup()
 {
     sysControl.begin();
@@ -17,12 +17,12 @@ void setup()
     sysControl.setExposureDelay(500); // same with 500µs delay between exposures
     sysControl.shoot();
 
-    sysControl.continousMode(true);   // start continously shooting
+    sysControl.continuosMode(true);   // start continuously shooting
     delay(1000);
-    sysControl.continousMode(false);  // stop after one second
+    sysControl.continuosMode(false);  // stop after one second
 
     delay(500);
-    sysControl.continousMode(true);   // start again
+    sysControl.continuosMode(true);   // start again
 }
 
 void loop()
diff --git a/third-party/TeensyTimerTool/examples/03_Applications/DoubleExposure/PulseGenerator.h b/third-party/TeensyTimerTool/examples/03_Applications/DoubleExposure/PulseGenerator.h
index db1f5ab..9a1ff34 100644
--- a/third-party/TeensyTimerTool/examples/03_Applications/DoubleExposure/PulseGenerator.h
+++ b/third-party/TeensyTimerTool/examples/03_Applications/DoubleExposure/PulseGenerator.h
@@ -7,7 +7,7 @@ class PulseGenerator
 {
  public:
     PulseGenerator();                             // constructor, initializes non hardware related stuff
-    void begin(unsigned pin);                     // intializes hardware related stuff
+    void begin(unsigned pin);                     // initializes hardware related stuff
     void schedulePulse(float delay, float width); // schedules a 'width µs' wide pulse after a waiting time of 'delay µs'. Non blocking.
 
  protected:
@@ -49,7 +49,7 @@ void PulseGenerator::callback()
     if (digitalReadFast(pin) == LOW)
     {
         digitalWriteFast(pin, HIGH);
-        pulseTimer.trigger(width);              // retrigger
+        pulseTimer.trigger(width);              // re-trigger
     } else
     {
         digitalWriteFast(pin, LOW);
diff --git a/third-party/TeensyTimerTool/examples/03_Applications/DoubleExposure/SystemController.h b/third-party/TeensyTimerTool/examples/03_Applications/DoubleExposure/SystemController.h
index efa2c19..c9091b2 100644
--- a/third-party/TeensyTimerTool/examples/03_Applications/DoubleExposure/SystemController.h
+++ b/third-party/TeensyTimerTool/examples/03_Applications/DoubleExposure/SystemController.h
@@ -9,7 +9,7 @@ class SystemController
     inline void begin();
     inline void shoot();
 
-    inline void continousMode(bool on);
+    inline void continuosMode(bool on);
     inline void setExposureDelay(unsigned delay);
 
  protected:
@@ -26,10 +26,10 @@ void SystemController::begin()
     constexpr unsigned repetitionRate = 15; // Hz
 
     constexpr unsigned preTrig1_pin = 1;
-    constexpr unsigned trig1_pin = 2;
+    constexpr unsigned trig1_pin    = 2;
     constexpr unsigned preTrig2_pin = 3;
-    constexpr unsigned trig2_pin = 4;
-    constexpr unsigned cam_pin = 5;
+    constexpr unsigned trig2_pin    = 4;
+    constexpr unsigned cam_pin      = 5;
 
     lCtrl1.begin(preTrig1_pin, trig1_pin, cam_pin);
     lCtrl2.begin(preTrig2_pin, trig2_pin, cam_pin);
@@ -45,13 +45,12 @@ void SystemController::shoot()
     lCtrl2.shoot();
 }
 
-void SystemController::continousMode(bool on)
+void SystemController::continuosMode(bool on)
 {
     if (on)
     {
         mainTimer.start();
-    }
-    else
+    } else
     {
         mainTimer.stop();
     }
diff --git a/third-party/TeensyTimerTool/library.json b/third-party/TeensyTimerTool/library.json
index 6852714..5fc6f3a 100644
--- a/third-party/TeensyTimerTool/library.json
+++ b/third-party/TeensyTimerTool/library.json
@@ -14,7 +14,7 @@
     "maintainer": true
   },
   "homepage": "https://github.com/luni64/TeensyTimerTool",
-  "version": "0.4.4",
+  "version": "1.0.0",
   "frameworks": "arduino",
   "platforms": "Teensy"
 }
diff --git a/third-party/TeensyTimerTool/library.properties b/third-party/TeensyTimerTool/library.properties
index c910ef7..1931bb0 100644
--- a/third-party/TeensyTimerTool/library.properties
+++ b/third-party/TeensyTimerTool/library.properties
@@ -1,5 +1,5 @@
 name=TeensyTimerTool
-version=0.4.4
+version=1.0.0
 author=luni64
 maintainer=luni64
 sentence=Generic Interface to Teensy Timers
diff --git a/third-party/TeensyTimerTool/src/API/baseTimer.h b/third-party/TeensyTimerTool/src/API/baseTimer.h
index f33caf7..45b8eaa 100644
--- a/third-party/TeensyTimerTool/src/API/baseTimer.h
+++ b/third-party/TeensyTimerTool/src/API/baseTimer.h
@@ -7,7 +7,7 @@
 #include <type_traits>
 
 #if defined(USE_TIME_LITERALS)
-#include "frequency.h"
+//#include "frequency.h"
 #include <chrono>
 #include <cmath>
 using namespace std::chrono_literals;
diff --git a/third-party/TeensyTimerTool/src/TimerModules/FTM/FTM.h b/third-party/TeensyTimerTool/src/TimerModules/FTM/FTM.h
index 32dbe47..0d6b07d 100644
--- a/third-party/TeensyTimerTool/src/TimerModules/FTM/FTM.h
+++ b/third-party/TeensyTimerTool/src/TimerModules/FTM/FTM.h
@@ -15,9 +15,9 @@ namespace TeensyTimerTool
         static bool isInitialized;
         inline static void isr() FASTRUN;
 
-        static constexpr FTM_r_t *r          = (FTM_r_t *)FTM_Info<moduleNr>::baseAdr;
         static constexpr unsigned maxChannel = FTM_Info<moduleNr>::nrOfChannels;
         static FTM_ChannelInfo channelInfo[maxChannel];
+        static FTM_r_t * const r;
 
         static_assert(moduleNr < 4, "Module number < 4 required");
     };
@@ -88,4 +88,8 @@ namespace TeensyTimerTool
 
     template <unsigned m>
     bool FTM_t<m>::isInitialized = false;
+
+    template <unsigned m>
+    FTM_r_t* const FTM_t<m>::r = (FTM_r_t *)FTM_Info<m>::baseAdr;
 } // namespace TeensyTimerTool
+
diff --git a/third-party/TeensyTimerTool/src/frequency.h.deactivated b/third-party/TeensyTimerTool/src/frequency.h.deactivated
new file mode 100644
index 0000000..832056c
--- /dev/null
+++ b/third-party/TeensyTimerTool/src/frequency.h.deactivated
@@ -0,0 +1,406 @@
+// <chrono> -*- C++ -*-
+
+// Copyright (C) 2008-2015 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// Under Section 7 of GPL version 3, you are granted additional
+// permissions described in the GCC Runtime Library Exception, version
+// 3.1, as published by the Free Software Foundation.
+
+// You should have received a copy of the GNU General Public License and
+// a copy of the GCC Runtime Library Exception along with this program;
+// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+// <http://www.gnu.org/licenses/>.
+
+#pragma once
+
+#include <chrono>
+#include <limits>
+#include <ratio>
+#include <type_traits>
+
+using std::common_type;
+using std::enable_if;
+using std::is_convertible;
+using std::ratio;
+using std::ratio_divide;
+
+namespace TeensyTimerTool
+{
+    template <typename _Rep, typename _Period = ratio<1>>
+    struct frequency;
+
+    template <typename _CT, typename _Period1, typename _Period2>
+    struct __frequency_common_type_wrapper
+    {
+     private:
+        typedef std::__static_gcd<_Period1::num, _Period2::num> __gcd_num;
+        typedef std::__static_gcd<_Period1::den, _Period2::den> __gcd_den;
+        typedef typename _CT::type __cr;
+        typedef ratio<__gcd_num::value,
+                      (_Period1::den / __gcd_den::value) * _Period2::den>
+            __r;
+
+     public:
+        typedef std::__success_type<TeensyTimerTool::frequency<__cr, __r>> type;
+    };
+
+    template <typename _Period1, typename _Period2>
+    struct __frequency_common_type_wrapper<std::__failure_type, _Period1, _Period2>
+    {
+        typedef std::__failure_type type;
+    };
+}
+
+namespace std
+{
+    template <typename _Rep1, typename _Period1, typename _Rep2, typename _Period2>
+    struct common_type<TeensyTimerTool::frequency<_Rep1, _Period1>, TeensyTimerTool::frequency<_Rep2, _Period2>>
+        : public TeensyTimerTool::__frequency_common_type_wrapper<typename __member_type_wrapper<std::common_type<_Rep1, _Rep2>>::type, _Period1, _Period2>::type
+    {
+    };
+}
+
+namespace TeensyTimerTool
+{
+    using namespace std::chrono;
+
+    // Primary template for frequency_cast impl.
+    template <typename _ToDur, typename _CF, typename _CR,
+              bool _NumIsOne = false, bool _DenIsOne = false>
+    struct __frequency_cast_impl
+    {
+        template <typename _Rep, typename _Period>
+        static constexpr _ToDur
+        __cast(const frequency<_Rep, _Period>& __d)
+        {
+            typedef typename _ToDur::rep __to_rep;
+            return _ToDur(static_cast<__to_rep>(static_cast<_CR>(__d.count()) * static_cast<_CR>(_CF::num) / static_cast<_CR>(_CF::den)));
+        }
+    };
+
+    template <typename _ToDur, typename _CF, typename _CR>
+    struct __frequency_cast_impl<_ToDur, _CF, _CR, true, true>
+    {
+        template <typename _Rep, typename _Period>
+        static constexpr _ToDur
+        __cast(const frequency<_Rep, _Period>& __d)
+        {
+            typedef typename _ToDur::rep __to_rep;
+            return _ToDur(static_cast<__to_rep>(__d.count()));
+        }
+    };
+
+    template <typename _ToDur, typename _CF, typename _CR>
+    struct __frequency_cast_impl<_ToDur, _CF, _CR, true, false>
+    {
+        template <typename _Rep, typename _Period>
+        static constexpr _ToDur
+        __cast(const frequency<_Rep, _Period>& __d)
+        {
+            typedef typename _ToDur::rep __to_rep;
+            return _ToDur(static_cast<__to_rep>(
+                static_cast<_CR>(__d.count()) / static_cast<_CR>(_CF::den)));
+        }
+    };
+
+    template <typename _ToDur, typename _CF, typename _CR>
+    struct __frequency_cast_impl<_ToDur, _CF, _CR, false, true>
+    {
+        template <typename _Rep, typename _Period>
+        static constexpr _ToDur
+        __cast(const frequency<_Rep, _Period>& __d)
+        {
+            typedef typename _ToDur::rep __to_rep;
+            return _ToDur(static_cast<__to_rep>(
+                static_cast<_CR>(__d.count()) * static_cast<_CR>(_CF::num)));
+        }
+    };
+
+    template <typename _Tp>
+    struct __is_frequency
+        : std::false_type
+    {
+    };
+
+    template <typename _Rep, typename _Period>
+    struct __is_frequency<frequency<_Rep, _Period>>
+        : std::true_type
+    {
+    };
+
+    /// duration_cast
+    template <typename _ToDur, typename _Rep, typename _Period>
+    constexpr typename enable_if<__is_frequency<_ToDur>::value, _ToDur>::type duration_cast(const frequency<_Rep, _Period>& __d)
+    {
+        typedef typename _ToDur::period __to_period;
+        typedef typename _ToDur::rep __to_rep;
+        typedef ratio_divide<_Period, __to_period> __cf;
+        typedef typename common_type<__to_rep, _Rep, intmax_t>::type __cr;
+        typedef __frequency_cast_impl<_ToDur, __cf, __cr, __cf::num == 1, __cf::den == 1> __dc;
+
+        return __dc::__cast(__d);
+    }
+
+    /// frequency
+    template <typename _Rep, typename _Period>
+    struct frequency
+    {
+        typedef _Rep rep;
+        typedef _Period period;
+
+        static_assert(!__is_frequency<_Rep>::value, "rep cannot be a frequency");
+        static_assert(std::chrono::__is_ratio<_Period>::value, "period must be a specialization of ratio");
+        static_assert(_Period::num > 0, "period must be positive");
+
+        // 20.11.5.1 construction / copy / destroy
+        constexpr frequency() = default;
+
+        // NB: Make constexpr implicit. This cannot be explicitly
+        // constexpr, as any UDT that is not a literal type with a
+        // constexpr copy constructor will be ill-formed.
+        frequency(const frequency&) = default;
+
+        template <typename _Rep2, typename = typename enable_if<is_convertible<_Rep2, rep>::value && (std::chrono::treat_as_floating_point<rep>::value || !std::chrono::treat_as_floating_point<_Rep2>::value)>::type>
+        constexpr explicit frequency(const _Rep2& __rep)
+            : __r(static_cast<rep>(__rep))
+        {
+        }
+
+        template <typename _Rep2, typename _Period2, typename = typename enable_if<treat_as_floating_point<rep>::value || (ratio_divide<_Period2, period>::den == 1 && !treat_as_floating_point<_Rep2>::value)>::type>
+        constexpr frequency(const frequency<_Rep2, _Period2>& __d)
+            : __r(duration_cast<frequency>(__d).count()) {}
+
+        ~frequency() = default;
+        frequency& operator=(const frequency&) = default;
+
+        // 20.11.5.2 observer
+        constexpr rep count() const { return __r; }
+
+        constexpr frequency operator+() const { return *this; }
+        constexpr frequency operator-() const { return frequency(-__r); }
+
+        frequency& operator++()
+        {
+            ++__r;
+            return *this;
+        }
+
+        frequency operator++(int)
+        {
+            return frequency(__r++);
+        }
+
+        frequency& operator--()
+        {
+            --__r;
+            return *this;
+        }
+
+        frequency
+        operator--(int)
+        {
+            return frequency(__r--);
+        }
+
+        frequency&
+        operator+=(const frequency& __d)
+        {
+            __r += __d.count();
+            return *this;
+        }
+
+        frequency&
+        operator-=(const frequency& __d)
+        {
+            __r -= __d.count();
+            return *this;
+        }
+
+        frequency&
+        operator*=(const rep& __rhs)
+        {
+            __r *= __rhs;
+            return *this;
+        }
+
+        frequency&
+        operator/=(const rep& __rhs)
+        {
+            __r /= __rhs;
+            return *this;
+        }
+
+        // DR 934.
+        template <typename _Rep2 = rep>
+        typename enable_if<!treat_as_floating_point<_Rep2>::value,
+                           frequency&>::type
+        operator%=(const rep& __rhs)
+        {
+            __r %= __rhs;
+            return *this;
+        }
+
+        template <typename _Rep2 = rep>
+        typename enable_if<!treat_as_floating_point<_Rep2>::value,
+                           frequency&>::type
+        operator%=(const frequency& __d)
+        {
+            __r %= __d.count();
+            return *this;
+        }
+
+        // 20.11.5.4 special values
+        static constexpr frequency
+        zero()
+        {
+            return frequency(duration_values<rep>::zero());
+        }
+
+        static constexpr frequency
+        min()
+        {
+            return frequency(duration_values<rep>::min());
+        }
+
+        static constexpr frequency
+        max()
+        {
+            return frequency(duration_values<rep>::max());
+        }
+
+     private:
+        rep __r;
+    };
+
+    template <typename _Rep1, typename _Period1, typename _Rep2, typename _Period2>
+    constexpr typename common_type<frequency<_Rep1, _Period1>, frequency<_Rep2, _Period2>>::type operator+(const frequency<_Rep1, _Period1>& __lhs, const frequency<_Rep2, _Period2>& __rhs)
+    {
+        typedef frequency<_Rep1, _Period1> __dur1;
+        typedef frequency<_Rep2, _Period2> __dur2;
+        typedef typename common_type<__dur1, __dur2>::type __cd;
+        return __cd(__cd(__lhs).count() + __cd(__rhs).count());
+    }
+
+    template <typename _Rep1, typename _Period1, typename _Rep2, typename _Period2>
+    constexpr typename common_type<frequency<_Rep1, _Period1>, frequency<_Rep2, _Period2>>::type operator-(const frequency<_Rep1, _Period1>& __lhs, const frequency<_Rep2, _Period2>& __rhs)
+    {
+        typedef frequency<_Rep1, _Period1> __dur1;
+        typedef frequency<_Rep2, _Period2> __dur2;
+        typedef typename common_type<__dur1, __dur2>::type __cd;
+        return __cd(__cd(__lhs).count() - __cd(__rhs).count());
+    }
+
+    template <typename _Rep1, typename _Period, typename _Rep2>
+    constexpr frequency<typename __common_rep_type<_Rep1, _Rep2>::type, _Period> operator*(const frequency<_Rep1, _Period>& __d, const _Rep2& __s)
+    {
+        typedef frequency<typename common_type<_Rep1, _Rep2>::type, _Period> __cd;
+        return __cd(__cd(__d).count() * __s);
+    }
+
+    template <typename _Rep1, typename _Rep2, typename _Period>
+    constexpr frequency<typename __common_rep_type<_Rep2, _Rep1>::type, _Period> operator*(const _Rep1& __s, const frequency<_Rep2, _Period>& __d)
+    {
+        return __d * __s;
+    }
+
+    template <typename _Rep1, typename _Period, typename _Rep2>
+    constexpr frequency<typename __common_rep_type<_Rep1, typename enable_if<!__is_frequency<_Rep2>::value, _Rep2>::type>::type, _Period> operator/(const frequency<_Rep1, _Period>& __d, const _Rep2& __s)
+    {
+        typedef frequency<typename common_type<_Rep1, _Rep2>::type, _Period> __cd;
+        return __cd(__cd(__d).count() / __s);
+    }
+
+    template <typename _Rep1, typename _Period1, typename _Rep2, typename _Period2>
+    constexpr typename common_type<_Rep1, _Rep2>::type operator/(const frequency<_Rep1, _Period1>& __lhs, const frequency<_Rep2, _Period2>& __rhs)
+    {
+        typedef frequency<_Rep1, _Period1> __dur1;
+        typedef frequency<_Rep2, _Period2> __dur2;
+        typedef typename common_type<__dur1, __dur2>::type __cd;
+        return __cd(__lhs).count() / __cd(__rhs).count();
+    }
+
+    // DR 934.
+    template <typename _Rep1, typename _Period, typename _Rep2>
+    constexpr frequency<typename __common_rep_type<_Rep1, typename enable_if<!__is_frequency<_Rep2>::value, _Rep2>::type>::type, _Period> operator%(const frequency<_Rep1, _Period>& __d, const _Rep2& __s)
+    {
+        typedef frequency<typename common_type<_Rep1, _Rep2>::type, _Period> __cd;
+        return __cd(__cd(__d).count() % __s);
+    }
+
+    template <typename _Rep1, typename _Period1, typename _Rep2, typename _Period2>
+    constexpr typename common_type<frequency<_Rep1, _Period1>, frequency<_Rep2, _Period2>>::type operator%(const frequency<_Rep1, _Period1>& __lhs, const frequency<_Rep2, _Period2>& __rhs)
+    {
+        typedef frequency<_Rep1, _Period1> __dur1;
+        typedef frequency<_Rep2, _Period2> __dur2;
+        typedef typename common_type<__dur1, __dur2>::type __cd;
+        return __cd(__cd(__lhs).count() % __cd(__rhs).count());
+    }
+
+    // comparisons
+    template <typename _Rep1, typename _Period1, typename _Rep2, typename _Period2>
+    constexpr bool operator==(const frequency<_Rep1, _Period1>& __lhs, const frequency<_Rep2, _Period2>& __rhs)
+    {
+        typedef frequency<_Rep1, _Period1> __dur1;
+        typedef frequency<_Rep2, _Period2> __dur2;
+        typedef typename common_type<__dur1, __dur2>::type __ct;
+        return __ct(__lhs).count() == __ct(__rhs).count();
+    }
+
+    template <typename _Rep1, typename _Period1, typename _Rep2, typename _Period2>
+    constexpr bool operator<(const frequency<_Rep1, _Period1>& __lhs, const frequency<_Rep2, _Period2>& __rhs)
+    {
+        typedef frequency<_Rep1, _Period1> __dur1;
+        typedef frequency<_Rep2, _Period2> __dur2;
+        typedef typename common_type<__dur1, __dur2>::type __ct;
+        return __ct(__lhs).count() < __ct(__rhs).count();
+    }
+
+    template <typename _Rep1, typename _Period1, typename _Rep2, typename _Period2>
+    constexpr bool operator!=(const frequency<_Rep1, _Period1>& __lhs, const frequency<_Rep2, _Period2>& __rhs)
+    {
+        return !(__lhs == __rhs);
+    }
+
+    template <typename _Rep1, typename _Period1, typename _Rep2, typename _Period2>
+    constexpr bool operator<=(const frequency<_Rep1, _Period1>& __lhs, const frequency<_Rep2, _Period2>& __rhs)
+    {
+        return !(__rhs < __lhs);
+    }
+
+    template <typename _Rep1, typename _Period1, typename _Rep2, typename _Period2>
+    constexpr bool operator>(const frequency<_Rep1, _Period1>& __lhs, const frequency<_Rep2, _Period2>& __rhs)
+    {
+        return __rhs < __lhs;
+    }
+
+    template <typename _Rep1, typename _Period1, typename _Rep2, typename _Period2>
+    constexpr bool operator>=(const frequency<_Rep1, _Period1>& __lhs, const frequency<_Rep2, _Period2>& __rhs)
+    {
+        return !(__lhs < __rhs);
+    }
+
+    using hertz = frequency<float>;
+    using kilohertz = frequency<float, std::kilo>;
+    using megahertz = frequency<float, std::mega>;
+    using gigahertz = frequency<float, std::giga>;
+
+    constexpr hertz operator""_Hz(long double hz) { return hertz{hz}; }
+    constexpr hertz operator""_Hz(uint64_t hz) { return hertz{hz}; }
+    constexpr kilohertz operator""_kHz(long double kHz) { return kilohertz{kHz}; }
+    constexpr kilohertz operator""_kHz(uint64_t kHz) { return kilohertz{kHz}; }
+    constexpr megahertz operator""_MHz(long double MHz) { return megahertz{MHz}; }
+    constexpr megahertz operator""_MHz(uint64_t MHz) { return megahertz{MHz}; }
+    constexpr gigahertz operator""_GHz(long double GHz) { return gigahertz{GHz}; }
+    constexpr gigahertz operator""_GHz(uint64_t GHz) { return gigahertz{GHz}; }
+}
diff --git a/third-party/TeensyTimerTool/src/helpers.h b/third-party/TeensyTimerTool/src/helpers.h
index cdedbad..1a8a90f 100644
--- a/third-party/TeensyTimerTool/src/helpers.h
+++ b/third-party/TeensyTimerTool/src/helpers.h
@@ -4,7 +4,6 @@
 #include <type_traits>
 
 #if defined(USE_TIME_LITERALS)
-#include "frequency.h"
 #include <chrono>
 #endif
 
@@ -27,15 +26,11 @@ namespace TeensyTimerTool
     template <class period_t, std::enable_if_t<std::chrono::__is_duration<period_t>::value, int> * = nullptr>
     float constexpr period2us(period_t v)
     {
+        using namespace std::chrono;
         return (duration_cast<duration<float, std::micro>>(v).count());
     }
 
-    // Frequency types (Hz, MHz...)
-    template <class period_t, std::enable_if_t<TeensyTimerTool::__is_frequency<period_t>::value, int> * = nullptr>
-    float constexpr period2us(period_t v)
-    {
-        return 1'000'000 / duration_cast<hertz>(v).count();
-    }
+
 #endif
 
 } // namespace TeensyTimerTool
\ No newline at end of file
diff --git a/third-party/TeensyTimerTool/test/main.cpp b/third-party/TeensyTimerTool/test/main.cpp
new file mode 100644
index 0000000..1a145de
--- /dev/null
+++ b/third-party/TeensyTimerTool/test/main.cpp
@@ -0,0 +1,17 @@
+#include "Arduino.h"
+
+// General =============================================================================================
+//#include "../lib/TeensyTimerTool/examples/01_Basic/HelloPeriodic/HelloPeriodic.ino"
+//#include "../lib/TeensyTimerTool/examples/01_Basic/HelloOneShot/HelloOneShot.ino"
+//#include "../lib/TeensyTimerTool/examples/01_Basic/UsingChronoDurations1/UsingChronoDurations1.ino"
+//#include "../lib/TeensyTimerTool/examples/01_Basic/UsingChronoDurations2/UsingChronoDurations2.ino"
+//#include "../lib/TeensyTimerTool/examples/02_Advanced/CallbackWithParams/CallbackWithParams.ino"
+//#include "../lib/TeensyTimerTool/examples/02_Advanced/UsingLambdas/UsingLambdas.ino"
+
+//T3.x ================================================================================================
+//#include "../lib/TeensyTimerTool/examples/03_Applications/DoubleExposure/DoubleExposure.ino"
+
+//T4.x ================================================================================================
+//#include "../lib/TeensyTimerTool/examples/01_Basic/MoreTimers/MoreTimers.ino"
+//#include "../lib/TeensyTimerTool/examples/01_Basic/RTC_Timer/RTC_Timer.ino"
+//#include "../lib/TeensyTimerTool/examples/99_Misc/PinInformation/PinInformation.ino"