This repository was archived by the owner on Jan 29, 2023. It is now read-only.
This repository was archived by the owner on Jan 29, 2023. It is now read-only.
Interrupt interval 2X requested interval #1
Closed
Description
Arduino IDE version 1.8.13
Adruino WiFI Rev 2
OS: Win 10
Context:
Actual interrupt delay is 2 times the programmed value. e.g., programmed value = 10 ms., actual value = 20 ms.
Steps to reproduce:
- Compile and run the Argument_None example with: #define TIMER1_INTERVAL_MS 11L, adding pin A0 to the
toggle1 code to observe the output on an oscilloscope connected to pin A0. - Observe that the waveform toggles at twice the programmed value (22 ms).
Works the same with any clock selected.
Am I doing something wrong?
/****************************************************************************************************************************
Argument_None.ino
For Arduino megaAVR ATMEGA4809-based boards (UNO WiFi Rev2, NANO_EVERY, etc. )
Written by Khoi Hoang
Built by Khoi Hoang https://github.com/khoih-prog/megaAVR_TimerInterrupt
Licensed under MIT license
Now with we can use these new 16 ISR-based timers, while consuming only 1 hwarware Timer.
Their independently-selected, maximum interval is practically unlimited (limited only by unsigned long miliseconds)
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.
Version: 1.3.0
Version Modified By Date Comments
------- ----------- ---------- -----------
1.0.0 K.Hoang 01/04/2021 Initial coding to support Arduino megaAVR ATmega4809-based boards (UNO WiFi Rev2, etc.)
1.1.0 K.Hoang 14/04/2021 Fix bug. Don't use v1.0.0
1.2.0 K.Hoang 17/04/2021 Selectable TCB Clock 16MHz, 8MHz or 250KHz depending on necessary accuracy
1.3.0 K.Hoang 17/04/2021 Fix TCB Clock bug. Don't use v1.2.0
*****************************************************************************************************************************/
// 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_16MHZ == true for 16MHz to Timer TCBx => shorter timer, but better accuracy
// Select USING_8MHZ == true for 8MHz to Timer TCBx => shorter timer, but better accuracy
// Select USING_250KHZ == true for 250KHz to Timer TCBx => shorter timer, but better accuracy
// Not select for default 250KHz to Timer TCBx => longer timer, but worse accuracy
#define USING_16MHZ false
#define USING_8MHZ false
#define USING_250KHZ true
#define USE_TIMER_0 false
#define USE_TIMER_1 true
#define USE_TIMER_2 false
#define USE_TIMER_3 false
#include "megaAVR_TimerInterrupt.h"
#define TIMER1_INTERVAL_MS 11L
#ifndef LED_BUILTIN
#define LED_BUILTIN 13
#endif
void TimerHandler1(void)
{
static bool toggle1 = false;
static bool started = false;
if (!started)
{
started = true;
pinMode(LED_BUILTIN, OUTPUT);
pinMode(A0, OUTPUT);
}
//timer interrupt toggles pin LED_BUILTIN
digitalWrite(LED_BUILTIN, toggle1);
digitalWrite(A0, toggle1);
toggle1 = !toggle1;
}
#if USE_TIMER_2
#define TIMER2_INTERVAL_MS 2
void TimerHandler2(void)
{
static bool toggle2 = false;
static bool started = false;
if (!started)
{
started = true;
pinMode(A0, OUTPUT);
}
//timer interrupt toggles outputPin
digitalWrite(A0, toggle2);
toggle2 = !toggle2;
}
#endif
void setup()
{
Serial.begin(115200);
while (!Serial);
Serial.print(F("\nStarting Argument_None on "));
Serial.println(BOARD_NAME);
Serial.println(MEGA_AVR_TIMER_INTERRUPT_VERSION);
Serial.print(F("CPU Frequency = ")); Serial.print(F_CPU / 1000000); Serial.println(F(" MHz"));
Serial.print(F("TCB Clock Frequency = "));
#if USING_16MHZ
Serial.println(F("16MHz for highest accuracy"));
#elif USING_8MHZ
Serial.println(F("8MHz for very high accuracy"));
#else
Serial.println(F("250KHz for lower accuracy but longer time"));
#endif
// Select Timer 1-2 for UNO, 0-5 for MEGA
// Timer 2 is 8-bit timer, only for higher frequency
ITimer1.init();
// Using ATmega328 used in UNO => 16MHz CPU clock ,
// For 16-bit timer 1, 3, 4 and 5, set frequency from 0.2385 to some KHz
// For 8-bit timer 2 (prescaler up to 1024, set frequency from 61.5Hz to some KHz
if (ITimer1.attachInterruptInterval(TIMER1_INTERVAL_MS, TimerHandler1))
{
Serial.print(F("Starting ITimer1 OK, millis() = ")); Serial.println(millis());
}
else
Serial.println(F("Can't set ITimer1. Select another freq. or timer"));
#if USE_TIMER_2
// Select Timer 1-2 for UNO, 0-5 for MEGA
// Timer 2 is 8-bit timer, only for higher frequency
ITimer2.init();
if (ITimer2.attachInterruptInterval(TIMER2_INTERVAL_MS, TimerHandler2))
{
Serial.print(F("Starting ITimer2 OK, millis() = ")); Serial.println(millis());
}
else
Serial.println(F("Can't set ITimer2. Select another freq. or timer"));
#endif
}
void loop()
{
}