增强现实AR>> megaAVR_TimerInterrupt>> 返回
项目作者： khoih-prog

项目描述 ：
This library enables you to use Interrupt from Hardware Timers on an ATmega4809-based board, such as Arduino UNO WiFi Rev2, AVR_NANO_EVERY, etc. It now supports 16 ISR-based timers, while consuming only 1 hardware Timer. Timers' interval is very long (ulong millisecs). The most important feature is they're ISR-based timers. Therefore, their executions are not blocked by bad-behaving functions or tasks. This important feature is absolutely necessary for mission-critical tasks.
高级语言： C++
项目地址: git://github.com/khoih-prog/megaAVR_TimerInterrupt.git
创建时间： 2021-04-03T18:12:04Z
项目社区：https://github.com/khoih-prog/megaAVR_TimerInterrupt
开源协议：MIT License
下载


megaAVR_TimerInterrupt Library

arduino-library-badge
GitHub release
GitHub
contributions welcome
GitHub issues

Donate to my libraries using BuyMeACoffee

—-

Table of Contents

—-

Important Change from v1.5.0

Please have a look at HOWTO Fix Multiple Definitions Linker Error

Why do we need this megaAVR_TimerInterrupt library

Features

This library enables you to use Interrupt from Hardware Timers on an ATmega4809-based boards, such as Arduino megaAVR : UNO WiFi Rev2, AVR_NANO_EVERY, etc.

As Hardware Timers are rare, and very precious assets of any board, this library now enables you to use up to 16 ISR-based Timers, while consuming only 1 Hardware Timer. Timers’ interval is very long (ulong millisecs).

Now with these new 16 ISR-based timers, the maximum interval is practically unlimited (limited only by unsigned long milliseconds) while the accuracy is nearly perfect compared to software timers.

The most important feature is they’re ISR-based timers. Therefore, their executions are not blocked by bad-behaving functions / tasks. This important feature is absolutely necessary for mission-critical tasks.

The ISR_Timer_Complex example will demonstrate the nearly perfect accuracy compared to software timers by printing the actual elapsed millisecs of each type of timers.

Being ISR-based timers, their executions are not blocked by bad-behaving functions / tasks, such as connecting to WiFi, Internet and Blynk services. You can also have many (up to 16) timers to use.

This non-being-blocked important feature is absolutely necessary for mission-critical tasks.

You’ll see blynkTimer Software is blocked while system is connecting to WiFi / Internet / Blynk, as well as by blocking task
in loop(), using delay() function as an example. The elapsed time then is very unaccurate

Why using ISR-based Hardware Timer Interrupt is better

Imagine you have a system with a mission-critical function, measuring water level and control the sump pump or doing something much more important. You normally use a software timer to poll, or even place the function in loop(). But what if another function is blocking the loop() or setup().

So your function might not be executed, and the result would be disastrous.

You’d prefer to have your function called, no matter what happening with other functions (busy loop, bug, etc.).

The correct choice is to use a Hardware Timer with Interrupt to call your function.

These hardware timers, using interrupt, still work even if other functions are blocking. Moreover, they are much more precise (certainly depending on clock frequency accuracy) than other software timers using millis() or micros(). That’s necessary if you need to measure some data requiring better accuracy.

Functions using normal software timers, relying on loop() and calling millis(), won’t work if the loop() or setup() is blocked by certain operation. For example, certain function is blocking while it’s connecting to WiFi or some services.

The catch is your function is now part of an ISR (Interrupt Service Routine), and must be lean / mean, and follow certain rules. More to read on:

HOWTO Attach Interrupt

Important Notes about ISR

  1. Inside the attached function, delay() won’t work and the value returned by millis() will not increment. Serial data received while in the function may be lost. You should declare as volatile any variables that you modify within the attached function.

  2. Typically global variables are used to pass data between an ISR and the main program. To make sure variables shared between an ISR and the main program are updated correctly, declare them as volatile.

Currently supported Boards

  • Arduino UNO WiFi Rev2, AVR_NANO_EVERY, etc.
  • ATmega4809-based boards.

—-

Prerequisites

  1. Arduino IDE 1.8.19+ for Arduino. GitHub release
  2. Arduino megaAVR core 1.8.7+ for Arduino megaAVR boards. Use Arduino Board Manager to install.
  3. MegaCoreX megaAVR core 1.1.0+ for Arduino megaAVR boards. GitHub release. Follow How to install.
  4. To use with certain example

—-

Installation

Use Arduino Library Manager

The best and easiest way is to use Arduino Library Manager. Search for megaAVR_TimerInterrupt, then select / install the latest version.
You can also use this link arduino-library-badge for more detailed instructions.

Manual Install

Another way to install is to:

  1. Navigate to megaAVR_TimerInterrupt page.
  2. Download the latest release megaAVR_TimerInterrupt-main.zip.
  3. Extract the zip file to megaAVR_TimerInterrupt-main directory
  4. Copy whole megaAVR_TimerInterrupt-main folder to Arduino libraries’ directory such as ~/Arduino/libraries/.

VS Code & PlatformIO:

  1. Install VS Code
  2. Install PlatformIO
  3. Install megaAVR_TimerInterrupt library by using Library Manager. Search for megaAVR_TimerInterrupt in Platform.io Author’s Libraries
  4. Use included platformio.ini file from examples to ensure that all dependent libraries will installed automatically. Please visit documentation for the other options and examples at Project Configuration File

—-

HOWTO Fix Multiple Definitions Linker Error

The current library implementation, using xyz-Impl.h instead of standard xyz.cpp, possibly creates certain Multiple Definitions Linker error in certain use cases.

You can include these .hpp files

  1. // Can be included as many times as necessary, without `Multiple Definitions` Linker Error
  2. #include "megaAVR_TimerInterrupt.hpp"   //https://github.com/khoih-prog/megaAVR_TimerInterrupt
  4. // Can be included as many times as necessary, without `Multiple Definitions` Linker Error
  5. #include "megaAVR_ISR_Timer.hpp"        //https://github.com/khoih-prog/megaAVR_TimerInterrupt

in many files. But be sure to use the following .h files in just 1 .h, .cpp or .ino file, which must not be included in any other file, to avoid Multiple Definitions Linker Error

  1. // To be included only in main(), .ino with setup() to avoid `Multiple Definitions` Linker Error
  2. #include "megaAVR_TimerInterrupt.h"     //https://github.com/khoih-prog/megaAVR_TimerInterrupt
  4. // To be included only in main(), .ino with setup() to avoid `Multiple Definitions` Linker Error
  5. #include "megaAVR_ISR_Timer.h"          //https://github.com/khoih-prog/megaAVR_TimerInterrupt

Check the new multiFileProject example for a HOWTO demo.

—-

More useful Information

1. Documents

  1. Arduino 101: Timers and Interrupts
  2. megaAVR0-series-Family-Data-Sheet

2. Timer TCB0-TCB3

TCB0-TCB3 are 16-bit timers.

—-

Usage

Before using any Timer, you have to make sure the Timer has not been used by any other purpose.

1. Using only Hardware Timer directly

1.1 Init Hardware Timer

  1. // Select USING_16MHZ     == true for  16MHz to Timer TCBx => shorter timer, but better accuracy
  2. // Select USING_8MHZ      == true for   8MHz to Timer TCBx => shorter timer, but better accuracy
  3. // Select USING_250KHZ    == true for 250KHz to Timer TCBx => shorter timer, but better accuracy
  4. // Not select for default 250KHz to Timer TCBx => longer timer,  but worse accuracy
  5. #define USING_16MHZ     true
  6. #define USING_8MHZ      false
  7. #define USING_250KHZ    false
  9. // Select the timers you're using, here ITimer1
  10. #define USE_TIMER_0     false
  11. #define USE_TIMER_1     true
  12. #define USE_TIMER_2     false
  13. #define USE_TIMER_3     false
  15. // Init timer ITimer1
  16. ITimer1.init();

1.2 Set Hardware Timer Interval and attach Timer Interrupt Handler function

Use one of these functions with interval in unsigned long milliseconds

  1. // interval (in ms) and duration (in milliseconds). Duration = 0 or not specified => run indefinitely
  2. template<typename TArg> bool setInterval(unsigned long interval, void (*callback)(TArg), TArg params, unsigned long duration = 0);
  4. // interval (in ms) and duration (in milliseconds). Duration = 0 or not specified => run indefinitely
  5. bool setInterval(unsigned long interval, timer_callback callback, unsigned long duration = 0);
  7. // Interval (in ms) and duration (in milliseconds). Duration = 0 or not specified => run indefinitely
  8. template<typename TArg> bool attachInterruptInterval(unsigned long interval, void (*callback)(TArg), TArg params, unsigned long duration = 0);
  10. // Interval (in ms) and duration (in milliseconds). Duration = 0 or not specified => run indefinitely
  11. bool attachInterruptInterval(unsigned long interval, timer_callback callback, unsigned long duration = 0)

as follows

  1. void TimerHandler1()
  2. {
  3.   // Doing something here inside ISR
  4. }
  6. #define TIMER1_INTERVAL_MS        50L
  8. void setup()
  9. {
  10.   ....
  12.   // Interval in unsigned long millisecs
  13.   if (ITimer1.attachInterruptInterval(TIMER1_INTERVAL_MS, TimerHandler1))
  14.     Serial.println("Starting  ITimer1 OK, millis() = " + String(millis()));
  15.   else
  16.     Serial.println("Can't set ITimer1. Select another freq. or timer");
  17. }

1.3 Set Hardware Timer Frequency and attach Timer Interrupt Handler function

Use one of these functions with frequency in float Hz

  1. // frequency (in hertz) and duration (in milliseconds). Duration = 0 or not specified => run indefinitely
  2. bool setFrequency(float frequency, timer_callback_p callback, /* void* */ uint32_t params, unsigned long duration = 0);
  4. // frequency (in hertz) and duration (in milliseconds). Duration = 0 or not specified => run indefinitely
  5. bool setFrequency(float frequency, timer_callback callback, unsigned long duration = 0);
  7. // frequency (in hertz) and duration (in milliseconds). Duration = 0 or not specified => run indefinitely
  8. template<typename TArg> bool attachInterrupt(float frequency, void (*callback)(TArg), TArg params, unsigned long duration = 0);
  10. // frequency (in hertz) and duration (in milliseconds). Duration = 0 or not specified => run indefinitely
  11. bool attachInterrupt(float frequency, timer_callback callback, unsigned long duration = 0);

as follows

  1. void TimerHandler1()
  2. {
  3.   // Doing something here inside ISR
  4. }
  6. #define TIMER1_FREQ_HZ        5555.555
  8. void setup()
  9. {
  10.   ....
  12.   // Frequency in float Hz
  13.   if (ITimer1.attachInterrupt(TIMER1_FREQ_HZ, TimerHandler1))
  14.     Serial.println("Starting  ITimer1 OK, millis() = " + String(millis()));
  15.   else
  16.     Serial.println("Can't set ITimer1. Select another freq. or timer");
  17. }

2. Using 16 ISR_based Timers from 1 Hardware Timer

2.1 Important Note

The 16 ISR_based Timers, designed for long timer intervals, only support using unsigned long millisec intervals. If you have to use much higher frequency or sub-millisecond interval, you have to use the Hardware Timers directly as in 1.3 Set Hardware Timer Frequency and attach Timer Interrupt Handler function

2.2 Init Hardware Timer and ISR-based Timer

  1. // Select USING_16MHZ     == true for  16MHz to Timer TCBx => shorter timer, but better accuracy
  2. // Select USING_8MHZ      == true for   8MHz to Timer TCBx => shorter timer, but better accuracy
  3. // Select USING_250KHZ    == true for 250KHz to Timer TCBx => shorter timer, but better accuracy
  4. // Not select for default 250KHz to Timer TCBx => longer timer,  but worse accuracy
  5. #define USING_16MHZ     true
  6. #define USING_8MHZ      false
  7. #define USING_250KHZ    false
  9. #define USE_TIMER_0     false
  10. #define USE_TIMER_1     true
  11. #define USE_TIMER_2     false
  12. #define USE_TIMER_3     false
  14. // Init ISR_Timer
  15. // Each ISR_Timer can service 16 different ISR-based timers
  16. ISR_Timer ISR_Timer1;

2.3 Set Hardware Timer Interval and attach Timer Interrupt Handler functions

  1. void TimerHandler()
  2. {
  3.   ISR_Timer1.run();
  4. }
  6. #define HW_TIMER_INTERVAL_MS          50L
  8. #define TIMER_INTERVAL_2S             2000L
  9. #define TIMER_INTERVAL_5S             5000L
  10. #define TIMER_INTERVAL_11S            11000L
  11. #define TIMER_INTERVAL_101S           101000L
  13. // In AVR, avoid doing something fancy in ISR, for example complex Serial.print with String() argument
  14. // The pure simple Serial.prints here are just for demonstration and testing. Must be eliminate in working environment
  15. // Or you can get this run-time error / crash
  16. void doingSomething2s()
  17. {
  18.   // Doing something here inside ISR every 2 seconds
  19. }
  21. void doingSomething5s()
  22. {
  23.   // Doing something here inside ISR every 5 seconds
  24. }
  26. void doingSomething11s()
  27. {
  28.   // Doing something here inside ISR  every 11 seconds
  29. }
  31. void doingSomething101s()
  32. {
  33.   // Doing something here inside ISR every 101 seconds
  34. }
  36. void setup()
  37. {
  38.   ....
  40.   // Interval in millisecs
  41.   if (ITimer.attachInterruptInterval(HW_TIMER_INTERVAL_MS, TimerHandler))
  42.   {
  43.     lastMillis = millis();
  44.     Serial.println("Starting ITimer OK, millis() = " + String(lastMillis));
  45.   }
  46.   else
  47.     Serial.println("Can't set ITimer correctly. Select another freq. or interval");
  49.   // Just to demonstrate, don't use too many ISR Timers if not absolutely necessary
  50.   // You can use up to 16 timer for each ISR_Timer
  51.   ISR_Timer1.setInterval(TIMER_INTERVAL_2S, doingSomething2s);
  52.   ISR_Timer1.setInterval(TIMER_INTERVAL_5S, doingSomething5s);
  53.   ISR_Timer1.setInterval(TIMER_INTERVAL_11S, doingSomething11s);
  54.   ISR_Timer1.setInterval(TIMER_INTERVAL_101S, doingSomething101s);
  55. }

—-

Examples:

  1. Argument_Complex
  2. Argument_None
  3. Argument_Simple
  4. Change_Interval.
  5. FakeAnalogWrite.
  6. ISR_16_Timers_Array_Complex.
  7. ISR_RPM_Measure
  8. Change_Interval_HF
  9. ISR_Timers_Array_Simple.
    1. RPM_Measure
    2. SwitchDebounce
    3. TimerDuration
    4. TimerInterruptTest
    5. multiFileProject New

Example ISR_16_Timers_Array_Complex

https://github.com/khoih-prog/megaAVR_TimerInterrupt/blob/59d45e43d51518de3034f22c8a2409afd0714e4e/examples/ISR_16_Timers_Array_Complex/ISR_16_Timers_Array_Complex.ino#L16-L373

—-

Debug Terminal Output Samples

1. ISR_16_Timers_Array_Complex on Arduino megaAVR Nano Every

The following is the sample terminal output when running example ISR_16_Timers_Array_Complex on Arduino megaAVR Nano Every to demonstrate the accuracy of ISR Hardware Timer, especially when system is very busy. The ISR timer is programmed for 2s, is activated exactly after 2.000s !!!

While software timer, **programmed for 2s, is activated after more than 10.000s in loop().

  1. Starting ISR_16_Timers_Array_Complex on megaAVR Nano Every
  2. megaAVR_TimerInterrupt v1.7.0
  3. CPU Frequency = 16 MHz
  4. TCB Clock Frequency = 250KHz for lower accuracy but longer time
  5. Starting  ITimer1 OK, millis() = 6
  6. SimpleTimer : 2, ms : 10006, Dms : 10006
  7. Timer : 0, programmed : 5000, actual : 5006
  8. Timer : 1, programmed : 10000, actual : 10010
  9. Timer : 2, programmed : 15000, actual : 0
  10. Timer : 3, programmed : 20000, actual : 0
  11. Timer : 4, programmed : 25000, actual : 0
  12. Timer : 5, programmed : 30000, actual : 0
  13. Timer : 6, programmed : 35000, actual : 0
  14. Timer : 7, programmed : 40000, actual : 0
  15. Timer : 8, programmed : 45000, actual : 0
  16. Timer : 9, programmed : 50000, actual : 0
  17. Timer : 10, programmed : 55000, actual : 0
  18. Timer : 11, programmed : 60000, actual : 0
  19. Timer : 12, programmed : 65000, actual : 0
  20. Timer : 13, programmed : 70000, actual : 0
  21. Timer : 14, programmed : 75000, actual : 0
  22. Timer : 15, programmed : 80000, actual : 0
  23. SimpleTimer : 2, ms : 20065, Dms : 10059
  24. Timer : 0, programmed : 5000, actual : 4994
  25. Timer : 1, programmed : 10000, actual : 9998
  26. Timer : 2, programmed : 15000, actual : 15014
  27. Timer : 3, programmed : 20000, actual : 20008
  28. Timer : 4, programmed : 25000, actual : 0
  29. Timer : 5, programmed : 30000, actual : 0
  30. Timer : 6, programmed : 35000, actual : 0
  31. Timer : 7, programmed : 40000, actual : 0
  32. Timer : 8, programmed : 45000, actual : 0
  33. Timer : 9, programmed : 50000, actual : 0
  34. Timer : 10, programmed : 55000, actual : 0
  35. Timer : 11, programmed : 60000, actual : 0
  36. Timer : 12, programmed : 65000, actual : 0
  37. Timer : 13, programmed : 70000, actual : 0
  38. Timer : 14, programmed : 75000, actual : 0
  39. Timer : 15, programmed : 80000, actual : 0
  40. SimpleTimer : 2, ms : 30125, Dms : 10060
  41. Timer : 0, programmed : 5000, actual : 4994
  42. Timer : 1, programmed : 10000, actual : 9998
  43. Timer : 2, programmed : 15000, actual : 14992
  44. Timer : 3, programmed : 20000, actual : 20008
  45. Timer : 4, programmed : 25000, actual : 25012
  46. Timer : 5, programmed : 30000, actual : 30006
  47. Timer : 6, programmed : 35000, actual : 0
  48. Timer : 7, programmed : 40000, actual : 0
  49. Timer : 8, programmed : 45000, actual : 0
  50. Timer : 9, programmed : 50000, actual : 0
  51. Timer : 10, programmed : 55000, actual : 0
  52. Timer : 11, programmed : 60000, actual : 0
  53. Timer : 12, programmed : 65000, actual : 0
  54. Timer : 13, programmed : 70000, actual : 0
  55. Timer : 14, programmed : 75000, actual : 0
  56. Timer : 15, programmed : 80000, actual : 0
  57. SimpleTimer : 2, ms : 40184, Dms : 10059
  58. Timer : 0, programmed : 5000, actual : 5004
  59. Timer : 1, programmed : 10000, actual : 10008
  60. Timer : 2, programmed : 15000, actual : 14992
  61. Timer : 3, programmed : 20000, actual : 20006
  62. Timer : 4, programmed : 25000, actual : 25012
  63. Timer : 5, programmed : 30000, actual : 30006
  64. Timer : 6, programmed : 35000, actual : 35010
  65. Timer : 7, programmed : 40000, actual : 40014
  66. Timer : 8, programmed : 45000, actual : 0
  67. Timer : 9, programmed : 50000, actual : 0
  68. Timer : 10, programmed : 55000, actual : 0
  69. Timer : 11, programmed : 60000, actual : 0
  70. Timer : 12, programmed : 65000, actual : 0
  71. Timer : 13, programmed : 70000, actual : 0
  72. Timer : 14, programmed : 75000, actual : 0
  73. Timer : 15, programmed : 80000, actual : 0
  74. SimpleTimer : 2, ms : 50245, Dms : 10061
  75. Timer : 0, programmed : 5000, actual : 5004
  76. Timer : 1, programmed : 10000, actual : 9998
  77. Timer : 2, programmed : 15000, actual : 15002
  78. Timer : 3, programmed : 20000, actual : 20006
  79. Timer : 4, programmed : 25000, actual : 25000
  80. Timer : 5, programmed : 30000, actual : 30006
  81. Timer : 6, programmed : 35000, actual : 35010
  82. Timer : 7, programmed : 40000, actual : 40014
  83. Timer : 8, programmed : 45000, actual : 45008
  84. Timer : 9, programmed : 50000, actual : 50012
  85. Timer : 10, programmed : 55000, actual : 0
  86. Timer : 11, programmed : 60000, actual : 0
  87. Timer : 12, programmed : 65000, actual : 0
  88. Timer : 13, programmed : 70000, actual : 0
  89. Timer : 14, programmed : 75000, actual : 0
  90. Timer : 15, programmed : 80000, actual : 0
  91. SimpleTimer : 2, ms : 60307, Dms : 10062
  92. Timer : 0, programmed : 5000, actual : 5004
  93. Timer : 1, programmed : 10000, actual : 9998
  94. Timer : 2, programmed : 15000, actual : 15002
  95. Timer : 3, programmed : 20000, actual : 19996
  96. Timer : 4, programmed : 25000, actual : 25000
  97. Timer : 5, programmed : 30000, actual : 30004
  98. Timer : 6, programmed : 35000, actual : 35010
  99. Timer : 7, programmed : 40000, actual : 40014
  100. Timer : 8, programmed : 45000, actual : 45008
  101. Timer : 9, programmed : 50000, actual : 50012
  102. Timer : 10, programmed : 55000, actual : 55006
  103. Timer : 11, programmed : 60000, actual : 60010
  104. Timer : 12, programmed : 65000, actual : 0
  105. Timer : 13, programmed : 70000, actual : 0
  106. Timer : 14, programmed : 75000, actual : 0
  107. Timer : 15, programmed : 80000, actual : 0
  108. SimpleTimer : 2, ms : 70369, Dms : 10062
  109. Timer : 0, programmed : 5000, actual : 4994
  110. Timer : 1, programmed : 10000, actual : 9998
  111. Timer : 2, programmed : 15000, actual : 15002
  112. Timer : 3, programmed : 20000, actual : 19996
  113. Timer : 4, programmed : 25000, actual : 25000
  114. Timer : 5, programmed : 30000, actual : 30004
  115. Timer : 6, programmed : 35000, actual : 34998
  116. Timer : 7, programmed : 40000, actual : 40014
  117. Timer : 8, programmed : 45000, actual : 45008
  118. Timer : 9, programmed : 50000, actual : 50012
  119. Timer : 10, programmed : 55000, actual : 55006
  120. Timer : 11, programmed : 60000, actual : 60010
  121. Timer : 12, programmed : 65000, actual : 65014
  122. Timer : 13, programmed : 70000, actual : 70008
  123. Timer : 14, programmed : 75000, actual : 0
  124. Timer : 15, programmed : 80000, actual : 0
  125. SimpleTimer : 2, ms : 80432, Dms : 10063
  126. Timer : 0, programmed : 5000, actual : 4994
  127. Timer : 1, programmed : 10000, actual : 9998
  128. Timer : 2, programmed : 15000, actual : 15002
  129. Timer : 3, programmed : 20000, actual : 19996
  130. Timer : 4, programmed : 25000, actual : 25000
  131. Timer : 5, programmed : 30000, actual : 30004
  132. Timer : 6, programmed : 35000, actual : 34998
  133. Timer : 7, programmed : 40000, actual : 39992
  134. Timer : 8, programmed : 45000, actual : 45008
  135. Timer : 9, programmed : 50000, actual : 50012
  136. Timer : 10, programmed : 55000, actual : 55006
  137. Timer : 11, programmed : 60000, actual : 60010
  138. Timer : 12, programmed : 65000, actual : 65014
  139. Timer : 13, programmed : 70000, actual : 70008
  140. Timer : 14, programmed : 75000, actual : 75012
  141. Timer : 15, programmed : 80000, actual : 80016

2. Change_Interval on Arduino megaAVR Nano Every

The following is the sample terminal output when running example Change_Interval on Arduino megaAVR Nano Every to demonstrate how to change Timer Interval on-the-fly

  1. Starting Change_Interval on megaAVR Nano Every
  2. megaAVR_TimerInterrupt v1.7.0
  3. CPU Frequency = 16 MHz
  4. TCB Clock Frequency = 250KHz for lower accuracy but longer time
  5. Starting  ITimer1 OK, millis() = 1
  6. Starting  ITimer2 OK, millis() = 4
  7. Time = 10001, Timer1Count = 97, Timer2Count = 49
  8. Time = 20002, Timer1Count = 195, Timer2Count = 99
  9. Changing Interval, Timer1 = 200,  Timer2 = 400
  10. Time = 30003, Timer1Count = 244, Timer2Count = 123
  11. Time = 40004, Timer1Count = 294, Timer2Count = 148
  12. Changing Interval, Timer1 = 100,  Timer2 = 200
  13. Time = 50006, Timer1Count = 391, Timer2Count = 197
  14. Time = 60007, Timer1Count = 489, Timer2Count = 247
  15. Changing Interval, Timer1 = 200,  Timer2 = 400
  16. Time = 70008, Timer1Count = 538, Timer2Count = 271
  17. Time = 80009, Timer1Count = 588, Timer2Count = 296
  18. Changing Interval, Timer1 = 100,  Timer2 = 200

3. ISR_16_Timers_Array_Complex on Arduino megaAVR Nano Every to show accuracy difference.

3.1. TCB Clock Frequency 16MHz for highest accuracy

  1. Starting ISR_16_Timers_Array_Complex on megaAVR Nano Every
  2. megaAVR_TimerInterrupt v1.7.0
  3. CPU Frequency = 16 MHz
  4. TCB Clock Frequency = 16MHz for highest accuracy
  5. Starting  ITimer1 OK, millis() = 6
  6. SimpleTimer : 2, ms : 10007, Dms : 10007
  7. Timer : 0, programmed : 5000, actual : 5000
  8. Timer : 1, programmed : 10000, actual : 10006
  9. Timer : 2, programmed : 15000, actual : 0
  10. Timer : 3, programmed : 20000, actual : 0
  11. Timer : 4, programmed : 25000, actual : 0
  12. Timer : 5, programmed : 30000, actual : 0
  13. Timer : 6, programmed : 35000, actual : 0
  14. Timer : 7, programmed : 40000, actual : 0
  15. Timer : 8, programmed : 45000, actual : 0
  16. Timer : 9, programmed : 50000, actual : 0
  17. Timer : 10, programmed : 55000, actual : 0
  18. Timer : 11, programmed : 60000, actual : 0
  19. Timer : 12, programmed : 65000, actual : 0
  20. Timer : 13, programmed : 70000, actual : 0
  21. Timer : 14, programmed : 75000, actual : 0
  22. Timer : 15, programmed : 80000, actual : 0
  23. SimpleTimer : 2, ms : 20066, Dms : 10059
  24. Timer : 0, programmed : 5000, actual : 5000
  25. Timer : 1, programmed : 10000, actual : 10000
  26. Timer : 2, programmed : 15000, actual : 15006
  27. Timer : 3, programmed : 20000, actual : 20006
  28. Timer : 4, programmed : 25000, actual : 0
  29. Timer : 5, programmed : 30000, actual : 0
  30. Timer : 6, programmed : 35000, actual : 0
  31. Timer : 7, programmed : 40000, actual : 0
  32. Timer : 8, programmed : 45000, actual : 0
  33. Timer : 9, programmed : 50000, actual : 0
  34. Timer : 10, programmed : 55000, actual : 0
  35. Timer : 11, programmed : 60000, actual : 0
  36. Timer : 12, programmed : 65000, actual : 0
  37. Timer : 13, programmed : 70000, actual : 0
  38. Timer : 14, programmed : 75000, actual : 0
  39. Timer : 15, programmed : 80000, actual : 0
  41. ...
  44. SimpleTimer : 2, ms : 211269, Dms : 10064
  45. Timer : 0, programmed : 5000, actual : 5000            <========== Very accurate @ clock 16MHz
  46. Timer : 1, programmed : 10000, actual : 10000
  47. Timer : 2, programmed : 15000, actual : 15000
  48. Timer : 3, programmed : 20000, actual : 20000
  49. Timer : 4, programmed : 25000, actual : 25000
  50. Timer : 5, programmed : 30000, actual : 30000
  51. Timer : 6, programmed : 35000, actual : 35000
  52. Timer : 7, programmed : 40000, actual : 40000
  53. Timer : 8, programmed : 45000, actual : 45000
  54. Timer : 9, programmed : 50000, actual : 50000
  55. Timer : 10, programmed : 55000, actual : 55000
  56. Timer : 11, programmed : 60000, actual : 60000
  57. Timer : 12, programmed : 65000, actual : 65000
  58. Timer : 13, programmed : 70000, actual : 70000
  59. Timer : 14, programmed : 75000, actual : 75000
  60. Timer : 15, programmed : 80000, actual : 80000
  61. SimpleTimer : 2, ms : 221333, Dms : 10064
  62. Timer : 0, programmed : 5000, actual : 5000
  63. Timer : 1, programmed : 10000, actual : 10000
  64. Timer : 2, programmed : 15000, actual : 15000
  65. Timer : 3, programmed : 20000, actual : 20000
  66. Timer : 4, programmed : 25000, actual : 25000
  67. Timer : 5, programmed : 30000, actual : 30000
  68. Timer : 6, programmed : 35000, actual : 35000
  69. Timer : 7, programmed : 40000, actual : 40000
  70. Timer : 8, programmed : 45000, actual : 45000
  71. Timer : 9, programmed : 50000, actual : 50000
  72. Timer : 10, programmed : 55000, actual : 55000
  73. Timer : 11, programmed : 60000, actual : 60000
  74. Timer : 12, programmed : 65000, actual : 65000
  75. Timer : 13, programmed : 70000, actual : 70000
  76. Timer : 14, programmed : 75000, actual : 75000
  77. Timer : 15, programmed : 80000, actual : 80000

3.2. TCB Clock Frequency 8MHz for very high accuracy

  2. Starting ISR_16_Timers_Array_Complex on megaAVR Nano Every
  3. megaAVR_TimerInterrupt v1.7.0
  4. CPU Frequency = 16 MHz
  5. TCB Clock Frequency = 8MHz for very high accuracy
  6. Starting  ITimer1 OK, millis() = 10
  7. SimpleTimer : 2, ms : 10011, Dms : 10011
  8. Timer : 0, programmed : 5000, actual : 5000
  9. Timer : 1, programmed : 10000, actual : 10011
  10. Timer : 2, programmed : 15000, actual : 0
  11. Timer : 3, programmed : 20000, actual : 0
  12. Timer : 4, programmed : 25000, actual : 0
  13. Timer : 5, programmed : 30000, actual : 0
  14. Timer : 6, programmed : 35000, actual : 0
  15. Timer : 7, programmed : 40000, actual : 0
  16. Timer : 8, programmed : 45000, actual : 0
  17. Timer : 9, programmed : 50000, actual : 0
  18. Timer : 10, programmed : 55000, actual : 0
  19. Timer : 11, programmed : 60000, actual : 0
  20. Timer : 12, programmed : 65000, actual : 0
  21. Timer : 13, programmed : 70000, actual : 0
  22. Timer : 14, programmed : 75000, actual : 0
  23. Timer : 15, programmed : 80000, actual : 0
  25. ...
  28. SimpleTimer : 2, ms : 160949, Dms : 10064
  29. Timer : 0, programmed : 5000, actual : 5000            <========== Very accurate @ clock 8MHz
  30. Timer : 1, programmed : 10000, actual : 10000
  31. Timer : 2, programmed : 15000, actual : 15000
  32. Timer : 3, programmed : 20000, actual : 20000
  33. Timer : 4, programmed : 25000, actual : 25000
  34. Timer : 5, programmed : 30000, actual : 30000
  35. Timer : 6, programmed : 35000, actual : 35000
  36. Timer : 7, programmed : 40000, actual : 40000
  37. Timer : 8, programmed : 45000, actual : 45000
  38. Timer : 9, programmed : 50000, actual : 50000
  39. Timer : 10, programmed : 55000, actual : 55000
  40. Timer : 11, programmed : 60000, actual : 60000
  41. Timer : 12, programmed : 65000, actual : 65000
  42. Timer : 13, programmed : 70000, actual : 70000
  43. Timer : 14, programmed : 75000, actual : 75000
  44. Timer : 15, programmed : 80000, actual : 80000
  45. SimpleTimer : 2, ms : 171013, Dms : 10064
  46. Timer : 0, programmed : 5000, actual : 5000
  47. Timer : 1, programmed : 10000, actual : 10000
  48. Timer : 2, programmed : 15000, actual : 15000
  49. Timer : 3, programmed : 20000, actual : 20000
  50. Timer : 4, programmed : 25000, actual : 25000
  51. Timer : 5, programmed : 30000, actual : 30000
  52. Timer : 6, programmed : 35000, actual : 35000
  53. Timer : 7, programmed : 40000, actual : 40000
  54. Timer : 8, programmed : 45000, actual : 45000
  55. Timer : 9, programmed : 50000, actual : 50000
  56. Timer : 10, programmed : 55000, actual : 55000
  57. Timer : 11, programmed : 60000, actual : 60000
  58. Timer : 12, programmed : 65000, actual : 65000
  59. Timer : 13, programmed : 70000, actual : 70000
  60. Timer : 14, programmed : 75000, actual : 75000
  61. Timer : 15, programmed : 80000, actual : 80000

3.3. TCB Clock Frequency 250KHz for lower accuracy but longer time

  1. Starting ISR_16_Timers_Array_Complex on megaAVR Nano Every
  2. megaAVR_TimerInterrupt v1.7.0
  3. CPU Frequency = 16 MHz
  4. TCB Clock Frequency = 250KHz for lower accuracy but longer time
  5. Starting  ITimer1 OK, millis() = 11
  6. SimpleTimer : 2, ms : 10012, Dms : 10012
  7. Timer : 0, programmed : 5000, actual : 5021
  8. Timer : 1, programmed : 10000, actual : 10015
  9. Timer : 2, programmed : 15000, actual : 0
  10. Timer : 3, programmed : 20000, actual : 0
  11. Timer : 4, programmed : 25000, actual : 0
  12. Timer : 5, programmed : 30000, actual : 0
  13. Timer : 6, programmed : 35000, actual : 0
  14. Timer : 7, programmed : 40000, actual : 0
  15. Timer : 8, programmed : 45000, actual : 0
  16. Timer : 9, programmed : 50000, actual : 0
  17. Timer : 10, programmed : 55000, actual : 0
  18. Timer : 11, programmed : 60000, actual : 0
  19. Timer : 12, programmed : 65000, actual : 0
  20. Timer : 13, programmed : 70000, actual : 0
  21. Timer : 14, programmed : 75000, actual : 0
  22. Timer : 15, programmed : 80000, actual : 0
  23. SimpleTimer : 2, ms : 20071, Dms : 10059
  24. Timer : 0, programmed : 5000, actual : 4994
  25. Timer : 1, programmed : 10000, actual : 9999
  26. Timer : 2, programmed : 15000, actual : 15020
  27. Timer : 3, programmed : 20000, actual : 20014
  28. Timer : 4, programmed : 25000, actual : 0
  29. Timer : 5, programmed : 30000, actual : 0
  30. Timer : 6, programmed : 35000, actual : 0
  31. Timer : 7, programmed : 40000, actual : 0
  32. Timer : 8, programmed : 45000, actual : 0
  33. Timer : 9, programmed : 50000, actual : 0
  34. Timer : 10, programmed : 55000, actual : 0
  35. Timer : 11, programmed : 60000, actual : 0
  36. Timer : 12, programmed : 65000, actual : 0
  37. Timer : 13, programmed : 70000, actual : 0
  38. Timer : 14, programmed : 75000, actual : 0
  39. Timer : 15, programmed : 80000, actual : 0
  41. ...
  44. SimpleTimer : 2, ms : 845278, Dms : 10063
  45. Timer : 0, programmed : 5000, actual : 4994            <========== Less accurate @ clock 250KHz
  46. Timer : 1, programmed : 10000, actual : 9997
  47. Timer : 2, programmed : 15000, actual : 15001
  48. Timer : 3, programmed : 20000, actual : 20005
  49. Timer : 4, programmed : 25000, actual : 25000
  50. Timer : 5, programmed : 30000, actual : 30004
  51. Timer : 6, programmed : 35000, actual : 34998
  52. Timer : 7, programmed : 40000, actual : 40001
  53. Timer : 8, programmed : 45000, actual : 44995
  54. Timer : 9, programmed : 50000, actual : 50000
  55. Timer : 10, programmed : 55000, actual : 55004
  56. Timer : 11, programmed : 60000, actual : 59998
  57. Timer : 12, programmed : 65000, actual : 64992
  58. Timer : 13, programmed : 70000, actual : 70005
  59. Timer : 14, programmed : 75000, actual : 75000
  60. Timer : 15, programmed : 80000, actual : 80004
  61. SimpleTimer : 2, ms : 855342, Dms : 10064
  62. Timer : 0, programmed : 5000, actual : 5004
  63. Timer : 1, programmed : 10000, actual : 9999
  64. Timer : 2, programmed : 15000, actual : 15003
  65. Timer : 3, programmed : 20000, actual : 20005
  66. Timer : 4, programmed : 25000, actual : 25000
  67. Timer : 5, programmed : 30000, actual : 30004
  68. Timer : 6, programmed : 35000, actual : 34998
  69. Timer : 7, programmed : 40000, actual : 40001
  70. Timer : 8, programmed : 45000, actual : 45007
  71. Timer : 9, programmed : 50000, actual : 50000
  72. Timer : 10, programmed : 55000, actual : 55004
  73. Timer : 11, programmed : 60000, actual : 59998
  74. Timer : 12, programmed : 65000, actual : 64992
  75. Timer : 13, programmed : 70000, actual : 70005
  76. Timer : 14, programmed : 75000, actual : 75000
  77. Timer : 15, programmed : 80000, actual : 80004

4. Change_Interval_HF on Arduino megaAVR Nano Every

The following is the sample terminal output when running example Change_Interval_HF on Arduino megaAVR Nano Every to demonstrate how to change High Frequency Timer Interval on-the-fly

  1. Starting Change_Interval_HF on megaAVR Nano Every
  2. megaAVR_TimerInterrupt v1.7.0
  3. CPU Frequency = 16 MHz
  4. TCB Clock Frequency = 16MHz for highest accuracy
  5. [TISR] TCB 1
  6. [TISR] ==================
  7. [TISR] Init, Timer = 1
  8. [TISR] CTRLB   = 0
  9. [TISR] CCMP    = 65535
  10. [TISR] INTCTRL = 0
  11. [TISR] CTRLA   = 1
  12. [TISR] ==================
  13. [TISR] Frequency = 10000.00 , CLK_TCB_FREQ = 16000000
  14. [TISR] setFrequency: _CCMPValueRemaining =  1600
  15. Starting ITimer1 OK, millis() = 12
  16. Frequency, Timer1 = 10000
  17. Time = 10001, Timer1Count = 99856
  18. Time = 20002, Timer1Count = 199807
  19. [TISR] Frequency = 5000.00 , CLK_TCB_FREQ = 16000000
  20. [TISR] setFrequency: _CCMPValueRemaining =  3200
  21. Changing Frequency, Timer1 = 5000
  22. Time = 30003, Timer1Count = 249792
  23. Time = 40004, Timer1Count = 299784
  24. [TISR] Frequency = 10000.00 , CLK_TCB_FREQ = 16000000
  25. [TISR] setFrequency: _CCMPValueRemaining =  1600
  26. Changing Frequency, Timer1 = 10000

5. ISR_16_Timers_Array_Complex on Arduino megaAVR Nano Every using MegaCoreX

The following is the sample terminal output when running example ISR_16_Timers_Array_Complex on Arduino megaAVR Nano Every using MegaCoreX to demonstrate the accuracy of ISR Hardware Timer, especially when system is very busy. The ISR timer is programmed for 2s, is activated exactly after 2.000s !!!

While software timer, **programmed for 2s, is activated after more than 10.000s in loop().

  1. Starting ISR_16_Timers_Array_Complex on MegaCoreX ATmega4809
  2. megaAVR_TimerInterrupt v1.7.0
  3. CPU Frequency = 16 MHz
  4. TCB Clock Frequency = 16MHz for highest accuracy
  5. [TISR] TCB1
  6. [TISR] ==================
  7. [TISR] Init, Timer = 1
  8. [TISR] CTRLB   = 0
  9. [TISR] CCMP    = 65535
  10. [TISR] INTCTRL = 0
  11. [TISR] CTRLA   = 1
  12. [TISR] ==================
  13. [TISR] Frequency = 200.00, CLK_TCB_FREQ = 16000000
  14. [TISR] setFrequency: _CCMPValueRemaining = 80000
  15. Starting  ITimer1 OK, millis() = 12
  16. SimpleTimer : 2, ms : 10013, Dms : 10013
  17. Timer : 0, programmed : 5000, actual : 5016
  18. Timer : 1, programmed : 10000, actual : 10016
  19. Timer : 2, programmed : 15000, actual : 0
  20. Timer : 3, programmed : 20000, actual : 0
  21. Timer : 4, programmed : 25000, actual : 0
  22. Timer : 5, programmed : 30000, actual : 0
  23. Timer : 6, programmed : 35000, actual : 0
  24. Timer : 7, programmed : 40000, actual : 0
  25. Timer : 8, programmed : 45000, actual : 0
  26. Timer : 9, programmed : 50000, actual : 0
  27. Timer : 10, programmed : 55000, actual : 0
  28. Timer : 11, programmed : 60000, actual : 0
  29. Timer : 12, programmed : 65000, actual : 0
  30. Timer : 13, programmed : 70000, actual : 0
  31. Timer : 14, programmed : 75000, actual : 0
  32. Timer : 15, programmed : 80000, actual : 0
  33. SimpleTimer : 2, ms : 20072, Dms : 10059
  34. Timer : 0, programmed : 5000, actual : 5000
  35. Timer : 1, programmed : 10000, actual : 10000
  36. Timer : 2, programmed : 15000, actual : 15016
  37. Timer : 3, programmed : 20000, actual : 20016
  38. Timer : 4, programmed : 25000, actual : 0
  39. Timer : 5, programmed : 30000, actual : 0
  40. Timer : 6, programmed : 35000, actual : 0
  41. Timer : 7, programmed : 40000, actual : 0
  42. Timer : 8, programmed : 45000, actual : 0
  43. Timer : 9, programmed : 50000, actual : 0
  44. Timer : 10, programmed : 55000, actual : 0
  45. Timer : 11, programmed : 60000, actual : 0
  46. Timer : 12, programmed : 65000, actual : 0
  47. Timer : 13, programmed : 70000, actual : 0
  48. Timer : 14, programmed : 75000, actual : 0
  49. Timer : 15, programmed : 80000, actual : 0
  50. SimpleTimer : 2, ms : 30132, Dms : 10060
  51. Timer : 0, programmed : 5000, actual : 5000
  52. Timer : 1, programmed : 10000, actual : 10001
  53. Timer : 2, programmed : 15000, actual : 15001
  54. Timer : 3, programmed : 20000, actual : 20016
  55. Timer : 4, programmed : 25000, actual : 25017
  56. Timer : 5, programmed : 30000, actual : 30017
  57. Timer : 6, programmed : 35000, actual : 0
  58. Timer : 7, programmed : 40000, actual : 0
  59. Timer : 8, programmed : 45000, actual : 0
  60. Timer : 9, programmed : 50000, actual : 0
  61. Timer : 10, programmed : 55000, actual : 0
  62. Timer : 11, programmed : 60000, actual : 0
  63. Timer : 12, programmed : 65000, actual : 0
  64. Timer : 13, programmed : 70000, actual : 0
  65. Timer : 14, programmed : 75000, actual : 0
  66. Timer : 15, programmed : 80000, actual : 0
  67. SimpleTimer : 2, ms : 40192, Dms : 10060
  68. Timer : 0, programmed : 5000, actual : 5000
  69. Timer : 1, programmed : 10000, actual : 10000
  70. Timer : 2, programmed : 15000, actual : 15001
  71. Timer : 3, programmed : 20000, actual : 20001
  72. Timer : 4, programmed : 25000, actual : 25017
  73. Timer : 5, programmed : 30000, actual : 30017
  74. Timer : 6, programmed : 35000, actual : 35017
  75. Timer : 7, programmed : 40000, actual : 40017
  76. Timer : 8, programmed : 45000, actual : 0
  77. Timer : 9, programmed : 50000, actual : 0
  78. Timer : 10, programmed : 55000, actual : 0
  79. Timer : 11, programmed : 60000, actual : 0
  80. Timer : 12, programmed : 65000, actual : 0
  81. Timer : 13, programmed : 70000, actual : 0
  82. Timer : 14, programmed : 75000, actual : 0
  83. Timer : 15, programmed : 80000, actual : 0
  84. SimpleTimer : 2, ms : 50253, Dms : 10061
  85. Timer : 0, programmed : 5000, actual : 5000
  86. Timer : 1, programmed : 10000, actual : 10000
  87. Timer : 2, programmed : 15000, actual : 15000
  88. Timer : 3, programmed : 20000, actual : 20001
  89. Timer : 4, programmed : 25000, actual : 25000
  90. Timer : 5, programmed : 30000, actual : 30017
  91. Timer : 6, programmed : 35000, actual : 35017
  92. Timer : 7, programmed : 40000, actual : 40017
  93. Timer : 8, programmed : 45000, actual : 45017
  94. Timer : 9, programmed : 50000, actual : 50017
  95. Timer : 10, programmed : 55000, actual : 0
  96. Timer : 11, programmed : 60000, actual : 0
  97. Timer : 12, programmed : 65000, actual : 0
  98. Timer : 13, programmed : 70000, actual : 0
  99. Timer : 14, programmed : 75000, actual : 0
  100. Timer : 15, programmed : 80000, actual : 0
  101. SimpleTimer : 2, ms : 60315, Dms : 10062
  102. Timer : 0, programmed : 5000, actual : 5000
  103. Timer : 1, programmed : 10000, actual : 10000
  104. Timer : 2, programmed : 15000, actual : 15000
  105. Timer : 3, programmed : 20000, actual : 20000
  106. Timer : 4, programmed : 25000, actual : 25000
  107. Timer : 5, programmed : 30000, actual : 30000
  108. Timer : 6, programmed : 35000, actual : 35017
  109. Timer : 7, programmed : 40000, actual : 40017
  110. Timer : 8, programmed : 45000, actual : 45017
  111. Timer : 9, programmed : 50000, actual : 50017
  112. Timer : 10, programmed : 55000, actual : 55017
  113. Timer : 11, programmed : 60000, actual : 60017
  114. Timer : 12, programmed : 65000, actual : 0
  115. Timer : 13, programmed : 70000, actual : 0
  116. Timer : 14, programmed : 75000, actual : 0
  117. Timer : 15, programmed : 80000, actual : 0
  118. SimpleTimer : 2, ms : 70377, Dms : 10062
  119. Timer : 0, programmed : 5000, actual : 5000
  120. Timer : 1, programmed : 10000, actual : 9996
  121. Timer : 2, programmed : 15000, actual : 15000
  122. Timer : 3, programmed : 20000, actual : 20000
  123. Timer : 4, programmed : 25000, actual : 25000
  124. Timer : 5, programmed : 30000, actual : 30000
  125. Timer : 6, programmed : 35000, actual : 34996
  126. Timer : 7, programmed : 40000, actual : 40017
  127. Timer : 8, programmed : 45000, actual : 45017
  128. Timer : 9, programmed : 50000, actual : 50017
  129. Timer : 10, programmed : 55000, actual : 55017
  130. Timer : 11, programmed : 60000, actual : 60017
  131. Timer : 12, programmed : 65000, actual : 65013
  132. Timer : 13, programmed : 70000, actual : 70013
  133. Timer : 14, programmed : 75000, actual : 0
  134. Timer : 15, programmed : 80000, actual : 0
  135. SimpleTimer : 2, ms : 80440, Dms : 10063
  136. Timer : 0, programmed : 5000, actual : 5000
  137. Timer : 1, programmed : 10000, actual : 10000
  138. Timer : 2, programmed : 15000, actual : 14996
  139. Timer : 3, programmed : 20000, actual : 19996
  140. Timer : 4, programmed : 25000, actual : 24996
  141. Timer : 5, programmed : 30000, actual : 30000
  142. Timer : 6, programmed : 35000, actual : 34996
  143. Timer : 7, programmed : 40000, actual : 39996
  144. Timer : 8, programmed : 45000, actual : 45017
  145. Timer : 9, programmed : 50000, actual : 50017
  146. Timer : 10, programmed : 55000, actual : 55017
  147. Timer : 11, programmed : 60000, actual : 60017
  148. Timer : 12, programmed : 65000, actual : 65013
  149. Timer : 13, programmed : 70000, actual : 70013
  150. Timer : 14, programmed : 75000, actual : 75013
  151. Timer : 15, programmed : 80000, actual : 80013

—-

Debug

Debug is enabled by default on Serial.

You can also change the debugging level from 0 to 3

  1. // These define's must be placed at the beginning before #include "megaAVR_TimerInterrupt.h"
  2. // _TIMERINTERRUPT_LOGLEVEL_ from 0 to 4
  3. // Don't define _TIMERINTERRUPT_LOGLEVEL_ > 0. Only for special ISR debugging only. Can hang the system.
  4. #define TIMER_INTERRUPT_DEBUG         0
  5. #define _TIMERINTERRUPT_LOGLEVEL_     0

Troubleshooting

If you get compilation errors, more often than not, you may need to install a newer version of the core for Arduino boards.

Sometimes, the library will only work if you update the board core to the latest version because I am using newly added functions.

—-

Issues

Submit issues to: megaAVR_TimerInterrupt issues

—-

TO DO

  1. Search for bug and improvement.

DONE

  1. Longer Interval for timers.
  2. Reduce code size if use less timers. Eliminate compiler warnings.
  3. Now supporting complex object pointer-type argument.
  4. 16 hardware-initiated software-enabled timers while using only 1 hardware timer.
  5. Fix some bugs in v1.0.0
  6. Add more examples.
  7. Similar library for ESP32, ESP8266, SAMD21/SAMD51, nRF52, Mbed-OS Nano-33-BLE, STM32
  8. Add support to ATmega4809-based boards, such as Arduino UNO WiFi Rev2, AVR_NANO_EVERY, etc.
  9. Selectable TCB Clock 16MHz, 8MHz or 250KHz depending on necessary accuracy
    1. Fix multiple-definitions linker error
    2. Optimize library code by using reference-passing instead of value-passing
    3. Add support to MegaCoreX core, including ATmega4809, ATmega4808, ATmega3209, ATmega3208, ATmega1609, ATmega1608, ATmega809 and ATmega808
    4. Use allman astyle and add utils

—-

Contributions and Thanks

Many thanks for everyone for bug reporting, new feature suggesting, testing and contributing to the development of this library. Especially to these people who have directly or indirectly contributed to this megaAVR_TimerInterrupt library

  1. Thanks to good work of Miguel Wisintainer for initiating, inspriring, working with, developing, debugging, testing and maintaining.
  2. Thanks to Bill Wuttke to report the issue Interrupt interval 2X requested interval #1 leading to new release v1.4.0 to fix bug in using higher frequencies than 250Hz
  3. Thanks to cattledogGH to report the issue Interrupt interval 2X requested interval #1 leading to new release v1.7.0 to fix bug disabling TCB0






tcpipchip
⭐️ Miguel Wisintainer
 wcwuttke
Bill Wuttke
 cattledogGH
cattledogGH

Contributing

If you want to contribute to this project:

  • Report bugs and errors
  • Ask for enhancements
  • Create issues and pull requests
  • Tell other people about this library

License

  • The library is licensed under MIT

Copyright 2021- Khoi Hoang