Skip to content
This repository was archived by the owner on Jan 29, 2023. It is now read-only.
/ Dx_TimerInterrupt Public archive

This library enables you to use Interrupt from Hardware Timers on Arduino AVRDx-based boards (AVR128Dx, AVR64Dx, AVR32Dx, etc.) using DxCore. These AVRDx 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 tim…

License

MIT license
1 star 0 forks Branches Tags Activity
Star
Notifications You must be signed in to change notification settings

khoih-prog/Dx_TimerInterrupt

BranchesTags

Repository files navigation

Dx_TimerInterrupt Library

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

Donate to my libraries using BuyMeACoffee

Table of Contents

Important Note for Arduino IDE

With some Arduino IDE versions, such as v1.8.19, upload directly via USB to some boards, such as Curiosity_AVR128DA48 or Curiosity_AVR128DB48 can't be done without unknown-to-me fix. We'll get the following error when uploading

avrdude: Version 6.3-20201216 Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/ Copyright (c) 2007-2014 Joerg Wunsch System wide configuration file is "/home/kh/.arduino15/packages/DxCore/hardware/megaavr/1.4.10/avrdude.conf" User configuration file is "/home/kh/.avrduderc" User configuration file does not exist or is not a regular file, skipping Using Port : usb Using Programmer : curiosity_updi avrdude: usbdev_open(): Found nEDBG CMSIS-DAP, serno: MCHP3280041800002682 avrdude: usbdev_open(): WARNING: failed to set configuration 1: Device or resource busy avrdude: Found CMSIS-DAP compliant device, using EDBG protocol avrdude: usbdev_send(): wrote -5 out of 912 bytes, err = Input/output error avrdude: jtag3_edbg_prepare(): failed to send command to serial port avrdude done. Thank you. the selected serial port does not exist or your board is not connected

We can use drag-and-drop method to drag-and-drop the compiled hex file to CURIOSITY virtual drive.

If success, The LED blinks slowly for 2 sec. The LED will blinks rapidly for 2 sec if failure

For example, to run Change_Interval example, use Arduino IDE to compile, and get the Change_Interval.ino.hex file. For Ubuntu Linux, the file is stored in directory /tmp/arduino_build_xxxxxx

After drag-and-drop the Change_Interval.ino.hex into CURIOSITY virtual drive, the code will run immediately if successfully loaded (LED blinks slowly)

Why do we need this Dx_TimerInterrupt library

Features

This library enables you to use Interrupt from Hardware Timers on Arduino AVRDx-based boards (AVR128Dx, AVR64Dx, AVR32Dx, etc.) using DxCore

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_16_Timers_Array_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

  • AVRDA-based boards (AVR128DA, AVR64DA, AVR32DA, etc.) using DxCore

  • AVRDB-based boards (AVR128DB, AVR64DB, AVR32DB, etc.) using DxCore

To be supported Boards

  • AVRDD-based boards (AVR64DD) using DxCore

  • tinyAVR boards using megaTinyCore

Prerequisites

  1. Arduino IDE 1.8.19+ for Arduino. GitHub release
  2. SpenceKonde DxCore core 1.4.10+ for Arduino AVRDx boards. GitHub release. Follow DxCore Installation.
  3. To use with certain example

Installation

Use Arduino Library Manager

The best and easiest way is to use Arduino Library Manager. Search for Dx_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 Dx_TimerInterrupt page.
  2. Download the latest release Dx_TimerInterrupt-main.zip.
  3. Extract the zip file to Dx_TimerInterrupt-main directory
  4. Copy whole Dx_TimerInterrupt-main folder to Arduino libraries' directory such as ~/Arduino/libraries/.

VS Code & PlatformIO:

  1. Install VS Code
  2. Install PlatformIO
  3. Install Dx_TimerInterrupt library by using Library Manager. Search for Dx_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

// Can be included as many times as necessary, without `Multiple Definitions` Linker Error #include "Dx_TimerInterrupt.hpp" //https://github.com/khoih-prog/Dx_TimerInterrupt // Can be included as many times as necessary, without `Multiple Definitions` Linker Error #include "Dx_ISR_Timer.hpp" //https://github.com/khoih-prog/Dx_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

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

Check the new multiFileProject example for a HOWTO demo.

More useful Information

1. Documents

  1. Arduino 101: Timers and Interrupts
  2. Getting Started with Timer/Counter Type B (TCB)
  3. DXCore README.md
  4. AVR128DA48-Curiosity-Nano-Hardware-User Guide
  5. AVR128DB48-Curiosity-Nano-Hardware-User Guide

2. Timer TCB0-TCB4

TCB0-TCB4 are 16-bit timers

The AVRDx boards with 14, 20, 28 or 32 pins, such as AVRDx28, will have only 3 TCB timers, (TCB0-TCB2)

The AVRDx with 48 pins, such as Curiosity Nano AVRDA48, Curiosity Nano AVRDB48, will have 4 TCB timers, (TCB0-TCB3)

The AVRDx with 64 pins, such as AVRDA64, AVRDB64, will have 5 TCB timers, (TCB0-TCB4)

The number of TCB timers will be automatically configured by the library.

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

// Select USING_FULL_CLOCK == true for 24/16MHz to Timer TCBx => shorter timer, but better accuracy // Select USING_HALF_CLOCK == true for 12/ 8MHz to Timer TCBx => shorter timer, but better accuracy // Select USING_250KHZ == true for 250KHz to Timer TCBx => longer timer, but worse accuracy // Not select for default 250KHz to Timer TCBx => longer timer, but worse accuracy #define USING_FULL_CLOCK true #define USING_HALF_CLOCK false #define USING_250KHZ false // Not supported now #define USE_TIMER_0 false #define USE_TIMER_1 true #define USE_TIMER_2 false // Normally used by millis(). Don't use #define USE_TIMER_3 false #define USE_TIMER_4 false #if USE_TIMER_0 #define CurrentTimer ITimer0 #elif USE_TIMER_1 #define CurrentTimer ITimer1 #elif USE_TIMER_2 #define CurrentTimer ITimer2 #elif USE_TIMER_3 #define CurrentTimer ITimer3 #elif USE_TIMER_4 #define CurrentTimer ITimer4 #else #error You must select one Timer #endif // Init timer CurrentTimer CurrentTimer.init();

1.2 Set Hardware Timer Interval and attach Timer Interrupt Handler function

Use one of these functions with interval in unsigned long milliseconds

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

as follows

void TimerHandler1() { // Doing something here inside ISR } #define TIMER1_INTERVAL_MS 50L void setup() { .... // Interval in unsigned long millisecs // Timer TCB2 is used for micros(), millis(), delay(), etc and can't be used ITimer1.init(); if (ITimer1.attachInterruptInterval(TIMER1_INTERVAL_MS, TimerHandler1)) { SerialDebug.print(F("Starting ITimer OK, millis() = ")); SerialDebug.println(millis()); } else SerialDebug.println(F("Can't set ITimer. Select another freq. or timer")); }

1.3 Set Hardware Timer Frequency and attach Timer Interrupt Handler function

Use one of these functions with frequency in float Hz

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

as follows

void TimerHandler1() { // Doing something here inside ISR } #define TIMER1_FREQ_HZ 5555.555 void setup() { .... // Frequency in float Hz if (ITimer1.attachInterrupt(TIMER1_FREQ_HZ, TimerHandler1)) { SerialDebug.print(F("Starting ITimer OK, millis() = ")); SerialDebug.println(millis()); } else SerialDebug.println("Can't set ITimer. Select another freq. or timer"); }

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

// Select USING_FULL_CLOCK == true for 24/16MHz to Timer TCBx => shorter timer, but better accuracy // Select USING_HALF_CLOCK == true for 12/ 8MHz to Timer TCBx => shorter timer, but better accuracy // Select USING_250KHZ == true for 250KHz to Timer TCBx => longer timer, but worse accuracy // Not select for default 250KHz to Timer TCBx => longer timer, but worse accuracy #define USING_FULL_CLOCK true #define USING_HALF_CLOCK false #define USING_250KHZ false // Not supported now #define USE_TIMER_0 false #define USE_TIMER_1 true #define USE_TIMER_2 false // Normally used by millis(). Don't use #define USE_TIMER_3 false #define USE_TIMER_4 false #if USE_TIMER_0 #define CurrentTimer ITimer0 #elif USE_TIMER_1 #define CurrentTimer ITimer1 #elif USE_TIMER_2 #define CurrentTimer ITimer2 #elif USE_TIMER_3 #define CurrentTimer ITimer3 #elif USE_TIMER_4 #define CurrentTimer ITimer4 #else #error You must select one Timer #endif // Init ISR_Timer // Each ISR_Timer can service 16 different ISR-based timers ISR_Timer ISR_Timer1;

2.3 Set Hardware Timer Interval and attach Timer Interrupt Handler functions

void TimerHandler() { ISR_Timer1.run(); } #define HW_TIMER_INTERVAL_MS 50L #define TIMER_INTERVAL_2S 2000L #define TIMER_INTERVAL_5S 5000L #define TIMER_INTERVAL_11S 11000L #define TIMER_INTERVAL_101S 101000L // In AVR, avoid doing something fancy in ISR, for example complex SerialDebug.print with String() argument // The pure simple SerialDebug.prints here are just for demonstration and testing. Must be eliminate in working environment // Or you can get this run-time error / crash void doingSomething2s() { // Doing something here inside ISR every 2 seconds } void doingSomething5s() { // Doing something here inside ISR every 5 seconds } void doingSomething11s() { // Doing something here inside ISR every 11 seconds } void doingSomething101s() { // Doing something here inside ISR every 101 seconds } void setup() { .... // Timer TCB2 is used for micros(), millis(), delay(), etc and can't be used CurrentTimer.init(); // Interval in millisecs if (CurrentTimer.attachInterruptInterval(HW_TIMER_INTERVAL_MS, TimerHandler)) { lastMillis = millis(); SerialDebug.print(F("Starting ITimer OK, millis() = ")); SerialDebug.println(millis()); } else SerialDebug.println(F("Can't set ITimer correctly. Select another freq. or interval")); // Just to demonstrate, don't use too many ISR Timers if not absolutely necessary // You can use up to 16 timer for each ISR_Timer ISR_Timer1.setInterval(TIMER_INTERVAL_2S, doingSomething2s); ISR_Timer1.setInterval(TIMER_INTERVAL_5S, doingSomething5s); ISR_Timer1.setInterval(TIMER_INTERVAL_11S, doingSomething11s); ISR_Timer1.setInterval(TIMER_INTERVAL_101S, doingSomething101s); }

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.
  10. RPM_Measure
  11. SwitchDebounce
  12. TimerDuration
  13. TimerInterruptTest
  14. multiFileProject

Example ISR_16_Timers_Array_Complex

Dx_TimerInterrupt/examples/ISR_16_Timers_Array_Complex/ISR_16_Timers_Array_Complex.ino

Lines 16 to 393 in 5da293e

// Important Note: To use drag-and-drop into CURIOSITY virtual drive if you can program via Arduino IDE
// For example, check https://ww1.microchip.com/downloads/en/DeviceDoc/AVR128DB48-Curiosity-Nano-HW-UserG-DS50003037A.pdf
#if !( defined(DXCORE) || defined(MEGATINYCORE) )
#error This is designed only for DXCORE or MEGATINYCORE megaAVR board! Please check your Tools->Board setting
#endif
// These define's must be placed at the beginning before #include "megaAVR_TimerInterrupt.h"
// _TIMERINTERRUPT_LOGLEVEL_ from 0 to 4
// Don't define _TIMERINTERRUPT_LOGLEVEL_ > 0. Only for special ISR debugging only. Can hang the system.
#define TIMER_INTERRUPT_DEBUG 0
#define _TIMERINTERRUPT_LOGLEVEL_ 0
// Select USING_FULL_CLOCK == true for 24/16MHz to Timer TCBx => shorter timer, but better accuracy
// Select USING_HALF_CLOCK == true for 12/ 8MHz to Timer TCBx => shorter timer, but better accuracy
// Select USING_250KHZ == true for 250KHz to Timer TCBx => longer timer, but worse accuracy
// Not select for default 250KHz to Timer TCBx => longer timer, but worse accuracy
#define USING_FULL_CLOCK false
#define USING_HALF_CLOCK true
#define USING_250KHZ false // Not supported now
#define USE_TIMER_0 false
#define USE_TIMER_1 true
#define USE_TIMER_2 false // Normally used by millis(). Don't use
#define USE_TIMER_3 false
#define USE_TIMER_4 false
#if USE_TIMER_0
#define CurrentTimer ITimer0
#elif USE_TIMER_1
#define CurrentTimer ITimer1
#elif USE_TIMER_2
#define CurrentTimer ITimer2
#elif USE_TIMER_3
#define CurrentTimer ITimer3
#elif USE_TIMER_4
#define CurrentTimer ITimer4
#else
#error You must select one Timer
#endif
// To be included only in main(), .ino with setup() to avoid `Multiple Definitions` Linker Error
#include "Dx_TimerInterrupt.h"
// To be included only in main(), .ino with setup() to avoid `Multiple Definitions` Linker Error
#include "Dx_ISR_Timer.h"
#include <SimpleTimer.h> // https://github.com/jfturcot/SimpleTimer
#ifdef LED_BUILTIN
#undef LED_BUILTIN
// To modify according to your board
// For Curiosity Nano AVR128DA48 => PIN_PC6
// For Curiosity Nano AVR128DB48 => PIN_PB3
#if defined(__AVR_AVR128DA48__)
#define LED_BUILTIN PIN_PC6 // PIN_PB3, 13
#elif defined(__AVR_AVR128DB48__)
#define LED_BUILTIN PIN_PB3 // PIN_PC6, 13
#else
// standard Arduino pin 13
#define LED_BUILTIN 13
#endif
#endif
#if defined(__AVR_AVR128DA48__)
#define SerialDebug Serial1
#elif defined(__AVR_AVR128DB48__)
#define SerialDebug Serial3
#else
// standard Serial
#define SerialDebug Serial
#endif
ISR_Timer ISR_Timer1;
#define LED_TOGGLE_INTERVAL_MS 1000L
// You have to use longer time here if having problem because Arduino AVR clock is low, 16MHz => lower accuracy.
// Tested OK with 1ms when not much load => higher accuracy.
#define TIMER1_INTERVAL_MS 5L
volatile uint32_t startMillis = 0;
void TimerHandler1()
{
static bool toggle = false;
static int timeRun = 0;
ISR_Timer1.run();
// Toggle LED every LED_TOGGLE_INTERVAL_MS = 2000ms = 2s
if (++timeRun == ((LED_TOGGLE_INTERVAL_MS) / TIMER1_INTERVAL_MS) )
{
timeRun = 0;
//timer interrupt toggles pin LED_BUILTIN
digitalWrite(LED_BUILTIN, toggle);
toggle = !toggle;
}
}
/////////////////////////////////////////////////
#define NUMBER_ISR_TIMERS 16
typedef void (*irqCallback) ();
/////////////////////////////////////////////////
#define USE_COMPLEX_STRUCT true
#if USE_COMPLEX_STRUCT
typedef struct
{
irqCallback irqCallbackFunc;
uint32_t TimerInterval;
unsigned long deltaMillis;
unsigned long previousMillis;
} ISRTimerData;
// Avoid doing something fancy in ISR, for example SerialDebug.print()
// The pure simple SerialDebug.prints here are just for demonstration and testing. Must be eliminate in working environment
// Or you can get this run-time error / crash
void doingSomething(int index);
#else
volatile unsigned long deltaMillis [NUMBER_ISR_TIMERS] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
volatile unsigned long previousMillis [NUMBER_ISR_TIMERS] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
// You can assign any interval for any timer here, in milliseconds
uint32_t TimerInterval[NUMBER_ISR_TIMERS] =
{
5000L, 10000L, 15000L, 20000L, 25000L, 30000L, 35000L, 40000L,
45000L, 50000L, 55000L, 60000L, 65000L, 70000L, 75000L, 80000L
};
void doingSomething(int index)
{
unsigned long currentMillis = millis();
deltaMillis[index] = currentMillis - previousMillis[index];
previousMillis[index] = currentMillis;
}
#endif
////////////////////////////////////
// Shared
////////////////////////////////////
void doingSomething0()
{
doingSomething(0);
}
void doingSomething1()
{
doingSomething(1);
}
void doingSomething2()
{
doingSomething(2);
}
void doingSomething3()
{
doingSomething(3);
}
void doingSomething4()
{
doingSomething(4);
}
void doingSomething5()
{
doingSomething(5);
}
void doingSomething6()
{
doingSomething(6);
}
void doingSomething7()
{
doingSomething(7);
}
void doingSomething8()
{
doingSomething(8);
}
void doingSomething9()
{
doingSomething(9);
}
void doingSomething10()
{
doingSomething(10);
}
void doingSomething11()
{
doingSomething(11);
}
void doingSomething12()
{
doingSomething(12);
}
void doingSomething13()
{
doingSomething(13);
}
void doingSomething14()
{
doingSomething(14);
}
void doingSomething15()
{
doingSomething(15);
}
#if USE_COMPLEX_STRUCT
ISRTimerData curISRTimerData[NUMBER_ISR_TIMERS] =
{
//irqCallbackFunc, TimerInterval, deltaMillis, previousMillis
{ doingSomething0, 5000L, 0, 0 },
{ doingSomething1, 10000L, 0, 0 },
{ doingSomething2, 15000L, 0, 0 },
{ doingSomething3, 20000L, 0, 0 },
{ doingSomething4, 25000L, 0, 0 },
{ doingSomething5, 30000L, 0, 0 },
{ doingSomething6, 35000L, 0, 0 },
{ doingSomething7, 40000L, 0, 0 },
{ doingSomething8, 45000L, 0, 0 },
{ doingSomething9, 50000L, 0, 0 },
{ doingSomething10, 55000L, 0, 0 },
{ doingSomething11, 60000L, 0, 0 },
{ doingSomething12, 65000L, 0, 0 },
{ doingSomething13, 70000L, 0, 0 },
{ doingSomething14, 75000L, 0, 0 },
{ doingSomething15, 80000L, 0, 0 }
};
void doingSomething(int index)
{
unsigned long currentMillis = millis();
curISRTimerData[index].deltaMillis = currentMillis - curISRTimerData[index].previousMillis;
curISRTimerData[index].previousMillis = currentMillis;
}
#else
irqCallback irqCallbackFunc[NUMBER_ISR_TIMERS] =
{
doingSomething0, doingSomething1, doingSomething2, doingSomething3,
doingSomething4, doingSomething5, doingSomething6, doingSomething7,
doingSomething8, doingSomething9, doingSomething10, doingSomething11,
doingSomething12, doingSomething13, doingSomething14, doingSomething15
};
#endif
////////////////////////////////////////////////
#define SIMPLE_TIMER_MS 2000L
// Init SimpleTimer
SimpleTimer simpleTimer;
// Here is software Timer, you can do somewhat fancy stuffs without many issues.
// But always avoid
// 1. Long delay() it just doing nothing and pain-without-gain wasting CPU power.Plan and design your code / strategy ahead
// 2. Very long "do", "while", "for" loops without predetermined exit time.
void simpleTimerDoingSomething2s()
{
static unsigned long previousMillis = startMillis;
unsigned long currMillis = millis();
SerialDebug.print(F("SimpleTimer : "));SerialDebug.print(SIMPLE_TIMER_MS / 1000);
SerialDebug.print(F(", ms : ")); SerialDebug.print(currMillis);
SerialDebug.print(F(", Dms : ")); SerialDebug.println(currMillis - previousMillis);
for (uint16_t i = 0; i < NUMBER_ISR_TIMERS; i++)
{
#if USE_COMPLEX_STRUCT
SerialDebug.print(F("Timer : ")); SerialDebug.print(i);
SerialDebug.print(F(", programmed : ")); SerialDebug.print(curISRTimerData[i].TimerInterval);
SerialDebug.print(F(", actual : ")); SerialDebug.println(curISRTimerData[i].deltaMillis);
#else
SerialDebug.print(F("Timer : ")); SerialDebug.print(i);
SerialDebug.print(F(", programmed : ")); SerialDebug.print(TimerInterval[i]);
SerialDebug.print(F(", actual : ")); SerialDebug.println(deltaMillis[i]);
#endif
}
previousMillis = currMillis;
}
void setup()
{
pinMode(LED_BUILTIN, OUTPUT);
SerialDebug.begin(115200);
while (!SerialDebug && millis() < 5000);
SerialDebug.print(F("\nStarting ISR_16_Timers_Array_Complex on ")); SerialDebug.println(BOARD_NAME);
SerialDebug.println(DX_TIMER_INTERRUPT_VERSION);
SerialDebug.print(F("CPU Frequency = ")); SerialDebug.print(F_CPU / 1000000); SerialDebug.println(F(" MHz"));
SerialDebug.print(F("TCB Clock Frequency = "));
#if USING_FULL_CLOCK
SerialDebug.println(F("Full clock (24/16MHz, etc) for highest accuracy"));
#elif USING_HALF_CLOCK
SerialDebug.println(F("Half clock (12/8MHz, etc.) for high accuracy"));
#else
SerialDebug.println(F("250KHz for lower accuracy but longer time"));
#endif
CurrentTimer.init();
if (CurrentTimer.attachInterruptInterval(TIMER1_INTERVAL_MS, TimerHandler1))
{
SerialDebug.print(F("Starting ITimer OK, millis() = ")); SerialDebug.println(millis());
}
else
SerialDebug.println(F("Can't set ITimer. Select another freq. or timer"));
//ISR_Timer1.setInterval(2000L, doingSomething2s);
//ISR_Timer1.setInterval(5000L, doingSomething5s);
// Just to demonstrate, don't use too many ISR Timers if not absolutely necessary
// You can use up to 16 timer for each ISR_Timer
for (uint16_t i = 0; i < NUMBER_ISR_TIMERS; i++)
{
#if USE_COMPLEX_STRUCT
curISRTimerData[i].previousMillis = startMillis;
ISR_Timer1.setInterval(curISRTimerData[i].TimerInterval, curISRTimerData[i].irqCallbackFunc);
#else
previousMillis[i] = startMillis;
ISR_Timer1.setInterval(TimerInterval[i], irqCallbackFunc[i]);
#endif
}
// You need this timer for non-critical tasks. Avoid abusing ISR if not absolutely necessary.
simpleTimer.setInterval(SIMPLE_TIMER_MS, simpleTimerDoingSomething2s);
}
#define BLOCKING_TIME_MS 10000L
void loop()
{
// This unadvised blocking task is used to demonstrate the blocking effects onto the execution and accuracy to Software timer
// You see the time elapse of ISR_Timer still accurate, whereas very unaccurate for Software Timer
// The time elapse for 2000ms software timer now becomes 3000ms (BLOCKING_TIME_MS)
// While that of ISR_Timer is still prefect.
delay(BLOCKING_TIME_MS);
// You need this Software timer for non-critical tasks. Avoid abusing ISR if not absolutely necessary
// You don't need to and never call ISR_Timer.run() here in the loop(). It's already handled by ISR timer.
simpleTimer.run();
}

Debug Terminal Output Samples

1. ISR_16_Timers_Array_Complex on Arduino AVR128DA

The following is the sample terminal output when running example ISR_16_Timers_Array_Complex on Arduino AVR128DA 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().

Starting ISR_16_Timers_Array_Complex on AVR128DA Dx_TimerInterrupt v1.1.3 CPU Frequency = 24 MHz TCB Clock Frequency = Full clock (24/16MHz, etc) for highest accuracy Starting ITimer OK, millis() = 13 SimpleTimer : 2, ms : 10013, Dms : 10013 Timer : 0, programmed : 5000, actual : 5017 Timer : 1, programmed : 10000, actual : 10017 Timer : 2, programmed : 15000, actual : 0 Timer : 3, programmed : 20000, actual : 0 Timer : 4, programmed : 25000, actual : 0 Timer : 5, programmed : 30000, actual : 0 Timer : 6, programmed : 35000, actual : 0 Timer : 7, programmed : 40000, actual : 0 Timer : 8, programmed : 45000, actual : 0 Timer : 9, programmed : 50000, actual : 0 Timer : 10, programmed : 55000, actual : 0 Timer : 11, programmed : 60000, actual : 0 Timer : 12, programmed : 65000, actual : 0 Timer : 13, programmed : 70000, actual : 0 Timer : 14, programmed : 75000, actual : 0 Timer : 15, programmed : 80000, actual : 0 SimpleTimer : 2, ms : 20072, Dms : 10059 Timer : 0, programmed : 5000, actual : 5000 Timer : 1, programmed : 10000, actual : 10000 Timer : 2, programmed : 15000, actual : 15017 Timer : 3, programmed : 20000, actual : 20017 Timer : 4, programmed : 25000, actual : 0 Timer : 5, programmed : 30000, actual : 0 Timer : 6, programmed : 35000, actual : 0 Timer : 7, programmed : 40000, actual : 0 Timer : 8, programmed : 45000, actual : 0 Timer : 9, programmed : 50000, actual : 0 Timer : 10, programmed : 55000, actual : 0 Timer : 11, programmed : 60000, actual : 0 Timer : 12, programmed : 65000, actual : 0 Timer : 13, programmed : 70000, actual : 0 Timer : 14, programmed : 75000, actual : 0 Timer : 15, programmed : 80000, actual : 0 ... SimpleTimer : 2, ms : 70376, Dms : 10062 Timer : 0, programmed : 5000, actual : 5000 Timer : 1, programmed : 10000, actual : 10000 Timer : 2, programmed : 15000, actual : 15000 Timer : 3, programmed : 20000, actual : 20000 Timer : 4, programmed : 25000, actual : 24996 Timer : 5, programmed : 30000, actual : 30000 Timer : 6, programmed : 35000, actual : 35000 Timer : 7, programmed : 40000, actual : 40013 Timer : 8, programmed : 45000, actual : 45013 Timer : 9, programmed : 50000, actual : 50013 Timer : 10, programmed : 55000, actual : 55013 Timer : 11, programmed : 60000, actual : 60013 Timer : 12, programmed : 65000, actual : 65013 Timer : 13, programmed : 70000, actual : 70013 Timer : 14, programmed : 75000, actual : 0 Timer : 15, programmed : 80000, actual : 0 SimpleTimer : 2, ms : 80439, Dms : 10063 Timer : 0, programmed : 5000, actual : 5000 Timer : 1, programmed : 10000, actual : 10000 Timer : 2, programmed : 15000, actual : 15000 Timer : 3, programmed : 20000, actual : 20000 Timer : 4, programmed : 25000, actual : 25000 Timer : 5, programmed : 30000, actual : 30000 Timer : 6, programmed : 35000, actual : 35000 Timer : 7, programmed : 40000, actual : 40000 Timer : 8, programmed : 45000, actual : 45013 Timer : 9, programmed : 50000, actual : 50013 Timer : 10, programmed : 55000, actual : 55013 Timer : 11, programmed : 60000, actual : 60013 Timer : 12, programmed : 65000, actual : 65013 Timer : 13, programmed : 70000, actual : 70013 Timer : 14, programmed : 75000, actual : 75013 Timer : 15, programmed : 80000, actual : 80013

2. ISR_16_Timers_Array_Complex on Arduino AVR128DA to show accuracy difference

2.1. TCB Clock Frequency Full clock for highest accuracy

Starting ISR_16_Timers_Array_Complex on AVR128DA Dx_TimerInterrupt v1.1.3 CPU Frequency = 24 MHz TCB Clock Frequency = Full clock (24/16MHz, etc) for highest accuracy Starting ITimer OK, millis() = 13 SimpleTimer : 2, ms : 10013, Dms : 10013 Timer : 0, programmed : 5000, actual : 5017 Timer : 1, programmed : 10000, actual : 10017 Timer : 2, programmed : 15000, actual : 0 Timer : 3, programmed : 20000, actual : 0 Timer : 4, programmed : 25000, actual : 0 Timer : 5, programmed : 30000, actual : 0 Timer : 6, programmed : 35000, actual : 0 Timer : 7, programmed : 40000, actual : 0 Timer : 8, programmed : 45000, actual : 0 Timer : 9, programmed : 50000, actual : 0 Timer : 10, programmed : 55000, actual : 0 Timer : 11, programmed : 60000, actual : 0 Timer : 12, programmed : 65000, actual : 0 Timer : 13, programmed : 70000, actual : 0 Timer : 14, programmed : 75000, actual : 0 Timer : 15, programmed : 80000, actual : 0 SimpleTimer : 2, ms : 20072, Dms : 10059 Timer : 0, programmed : 5000, actual : 5000 Timer : 1, programmed : 10000, actual : 10000 Timer : 2, programmed : 15000, actual : 15017 Timer : 3, programmed : 20000, actual : 20017 Timer : 4, programmed : 25000, actual : 0 Timer : 5, programmed : 30000, actual : 0 Timer : 6, programmed : 35000, actual : 0 Timer : 7, programmed : 40000, actual : 0 Timer : 8, programmed : 45000, actual : 0 Timer : 9, programmed : 50000, actual : 0 Timer : 10, programmed : 55000, actual : 0 Timer : 11, programmed : 60000, actual : 0 Timer : 12, programmed : 65000, actual : 0 Timer : 13, programmed : 70000, actual : 0 Timer : 14, programmed : 75000, actual : 0 Timer : 15, programmed : 80000, actual : 0 ... SimpleTimer : 2, ms : 70376, Dms : 10062 Timer : 0, programmed : 5000, actual : 5000 Timer : 1, programmed : 10000, actual : 10000 Timer : 2, programmed : 15000, actual : 15000 Timer : 3, programmed : 20000, actual : 20000 Timer : 4, programmed : 25000, actual : 24996 Timer : 5, programmed : 30000, actual : 30000 Timer : 6, programmed : 35000, actual : 35000 Timer : 7, programmed : 40000, actual : 40013 Timer : 8, programmed : 45000, actual : 45013 Timer : 9, programmed : 50000, actual : 50013 Timer : 10, programmed : 55000, actual : 55013 Timer : 11, programmed : 60000, actual : 60013 Timer : 12, programmed : 65000, actual : 65013 Timer : 13, programmed : 70000, actual : 70013 Timer : 14, programmed : 75000, actual : 0 Timer : 15, programmed : 80000, actual : 0 SimpleTimer : 2, ms : 80439, Dms : 10063 Timer : 0, programmed : 5000, actual : 5000 Timer : 1, programmed : 10000, actual : 10000 Timer : 2, programmed : 15000, actual : 15000 Timer : 3, programmed : 20000, actual : 20000 Timer : 4, programmed : 25000, actual : 25000 Timer : 5, programmed : 30000, actual : 30000 Timer : 6, programmed : 35000, actual : 35000 Timer : 7, programmed : 40000, actual : 40000 Timer : 8, programmed : 45000, actual : 45013 Timer : 9, programmed : 50000, actual : 50013 Timer : 10, programmed : 55000, actual : 55013 Timer : 11, programmed : 60000, actual : 60013 Timer : 12, programmed : 65000, actual : 65013 Timer : 13, programmed : 70000, actual : 70013 Timer : 14, programmed : 75000, actual : 75013 Timer : 15, programmed : 80000, actual : 80013

2.2. TCB Clock Frequency Half clock for high accuracy

Starting ISR_16_Timers_Array_Complex on AVR128DA Dx_TimerInterrupt v1.1.3 CPU Frequency = 24 MHz TCB Clock Frequency = Half clock (12/8MHz, etc.) for high accuracy Starting ITimer OK, millis() = 12 SimpleTimer : 2, ms : 10013, Dms : 10013 Timer : 0, programmed : 5000, actual : 5015 Timer : 1, programmed : 10000, actual : 10015 Timer : 2, programmed : 15000, actual : 0 Timer : 3, programmed : 20000, actual : 0 Timer : 4, programmed : 25000, actual : 0 Timer : 5, programmed : 30000, actual : 0 Timer : 6, programmed : 35000, actual : 0 Timer : 7, programmed : 40000, actual : 0 Timer : 8, programmed : 45000, actual : 0 Timer : 9, programmed : 50000, actual : 0 Timer : 10, programmed : 55000, actual : 0 Timer : 11, programmed : 60000, actual : 0 Timer : 12, programmed : 65000, actual : 0 Timer : 13, programmed : 70000, actual : 0 Timer : 14, programmed : 75000, actual : 0 Timer : 15, programmed : 80000, actual : 0 SimpleTimer : 2, ms : 20072, Dms : 10059 Timer : 0, programmed : 5000, actual : 5000 Timer : 1, programmed : 10000, actual : 10000 Timer : 2, programmed : 15000, actual : 15015 Timer : 3, programmed : 20000, actual : 20015 Timer : 4, programmed : 25000, actual : 0 Timer : 5, programmed : 30000, actual : 0 Timer : 6, programmed : 35000, actual : 0 Timer : 7, programmed : 40000, actual : 0 Timer : 8, programmed : 45000, actual : 0 Timer : 9, programmed : 50000, actual : 0 Timer : 10, programmed : 55000, actual : 0 Timer : 11, programmed : 60000, actual : 0 Timer : 12, programmed : 65000, actual : 0 Timer : 13, programmed : 70000, actual : 0 Timer : 14, programmed : 75000, actual : 0 Timer : 15, programmed : 80000, actual : 0 ... SimpleTimer : 2, ms : 80439, Dms : 10063 Timer : 0, programmed : 5000, actual : 5000 Timer : 1, programmed : 10000, actual : 10000 Timer : 2, programmed : 15000, actual : 15001 Timer : 3, programmed : 20000, actual : 20001 Timer : 4, programmed : 25000, actual : 25001 Timer : 5, programmed : 30000, actual : 30000 Timer : 6, programmed : 35000, actual : 35001 Timer : 7, programmed : 40000, actual : 40001 Timer : 8, programmed : 45000, actual : 45015 Timer : 9, programmed : 50000, actual : 50015 Timer : 10, programmed : 55000, actual : 55015 Timer : 11, programmed : 60000, actual : 60015 Timer : 12, programmed : 65000, actual : 65016 Timer : 13, programmed : 70000, actual : 70016 Timer : 14, programmed : 75000, actual : 75016 Timer : 15, programmed : 80000, actual : 80016

3. Change_Interval_HF on Arduino AVR128DA

The following is the sample terminal output when running example Change_Interval_HF on Arduino AVR128DA to demonstrate how to change High Frequency Timer Interval on-the-fly

Starting Change_Interval_HF on AVR128DA Dx_TimerInterrupt v1.1.3 CPU Frequency = 24 MHz TCB Clock Frequency = Full clock (24/16MHz, etc) for highest accuracy Starting ITimer OK, millis() = 12 Frequency, Timer = 50 Time = 1001, Timer1Count = 49 Time = 2002, Timer1Count = 99 Time = 3003, Timer1Count = 149 Time = 4004, Timer1Count = 199 Time = 5005, Timer1Count = 249 Changing Frequency, Timer = 25 Time = 6006, Timer1Count = 274 Time = 7007, Timer1Count = 299 Time = 8008, Timer1Count = 324 Time = 9009, Timer1Count = 349 Time = 10010, Timer1Count = 374 Changing Frequency, Timer = 16 Time = 11011, Timer1Count = 390 Time = 12012, Timer1Count = 406 Time = 13013, Timer1Count = 422 Time = 14014, Timer1Count = 438 Time = 15015, Timer1Count = 454 Changing Frequency, Timer = 12 Time = 16016, Timer1Count = 466 Time = 17017, Timer1Count = 478 Time = 18018, Timer1Count = 490 Time = 19019, Timer1Count = 502 Time = 20020, Timer1Count = 514 Changing Frequency, Timer = 10 Time = 21021, Timer1Count = 524 Time = 22022, Timer1Count = 534 Time = 23023, Timer1Count = 544 Time = 24024, Timer1Count = 554 Time = 25025, Timer1Count = 564 Changing Frequency, Timer = 8 Time = 26026, Timer1Count = 572 Time = 27027, Timer1Count = 580 Time = 28028, Timer1Count = 588 Time = 29029, Timer1Count = 596 Time = 30030, Timer1Count = 604 Changing Frequency, Timer = 7 Time = 31031, Timer1Count = 611 Time = 32032, Timer1Count = 618 Time = 33033, Timer1Count = 625 Time = 34034, Timer1Count = 632 Time = 35035, Timer1Count = 639 Changing Frequency, Timer = 6 Time = 36036, Timer1Count = 645 Time = 37037, Timer1Count = 651 Time = 38038, Timer1Count = 657 Time = 39039, Timer1Count = 663 Time = 40040, Timer1Count = 669

Debug

Debug is enabled by default on Serial1 for Curiosity Nano AVRDA and Serial3 for Curiosity Nano AVRDB.

You can also change the debugging level from 0 to 4

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

TO DO

  1. Search for bug and improvement
  2. Add support to AVRDD-based boards (AVR64DD) using DxCore
  3. Add support to tinyAVRDD-based boards using megaTinyCore
  4. Add support to 250KHz Timer Frequency

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. Add support to AVRDx-based boards (AVR128Dx, AVR64Dx, AVR32Dx, etc.) using DxCore
  6. Selectable TCB Clock FULL, HALF depending on necessary accuracy
  7. Fix multiple-definitions linker error
  8. Optimize library code by using reference-passing instead of value-passing
  9. Improve and customize examples for Curiosity Nano AVRDA/AVRDB boards to use on-board LED and SW
  10. Add notes howto upload by drag-and-drop to CURIOSITY virtual drive
  11. Using Serial3 for debugging with Curiosity Nano AVRDB, and Serial1 for debugging with Curiosity Nano AVRDA
  12. Fix bug giving error when using TCB0 (USE_TIMER_0 == true)
  13. Fix bug causing system crash when using _TIMERINTERRUPT_LOGLEVEL_ > 0

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 Dx_TimerInterrupt library

  1. Thanks to good work of Spence Konde (aka Dr. Azzy) for the DxCore and megaTinyCore
  2. Thanks to LaurentR59 to request the enhancement Support for DX CORE CPU and MightyCORE CPU possible? #8 leading to this new library
SpenceKonde
⭐️⭐️ Spence Konde
 LaurentR59
LaurentR59

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

Copyright 2022- Khoi Hoang

About

This library enables you to use Interrupt from Hardware Timers on Arduino AVRDx-based boards (AVR128Dx, AVR64Dx, AVR32Dx, etc.) using DxCore. These AVRDx 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 tim…

Topics

timer accuracy isr non-blocking timer-interrupt mission-critical megaavr hardware-timers avr-da tinyavr avr-db avr-dd dxcore avr64dx avr128dx avr32dx megatinycore dx-timerinterrupt tcb-timers

Resources

Readme

License

MIT license

Contributing

Contributing
Activity

Stars

1 star

Watchers

1 watching

Forks

0 forks
Report repository

Releases 5

v1.1.3 to fix bug giving error when using TCB0 and bug causing system crash when using `_TIMERINTERRUPT_LOGLEVEL_ > 0` Latest
Aug 27, 2022
+ 4 releases

Packages

No packages published

Languages