![]() Make sure your timeflag is declared as volatile since it's being changed inside an interrupt and checked outside the interrupt. Many Arduino functions uses timers, for example the time functions: delay(), millis() and micros() and. compare match register 16,000,000Hz/ (prescaler desired interrupt. Simple non-blocking timer library for calling functions in / at / every specified units of time. Timerflag = 0 // reset for next interrupt low level hardware stuff is hidden by the Arduino API. Timer0 - An 8 bit timer used by Arduino functions delay(), millis() and micros(). Timer library for delaying function calls. ![]() esptimer set of APIs provides one-shot and periodic timers, microsecond time resolution, and 64-bit range. ![]() Pseudocode: volatile uint8_t timerflag = 0 Raising the timer interrupt’s priority can reduce the timer processing delay caused by interrupt latency. Here we discuss how to use millis () and micros () and their major advantages compared to delay (). When you're talking microseconds, it's especially important to get out of that ISR quickly. Arduino Tutorials 3 Comments One of our most popular blog posts right now this is called Arduino Tutorial: Using millis () Instead of delay (). So without counting instruction clock cycles, I think I'd pursue the line of thought from your last statement - lighten the load in that interrupt by just setting a flag and then exit. And DigitalWrite isn't as fast as you think. There's some overhead in entering and exiting the interrupt. That is mandatory if you need to measure some data requiring better accuracy. Moreover, they are much more precise (certainly depending on clock frequency accuracy) than other software timers using millis() or micros(). It now supports 16 ISR-based timers, while consuming only 1 Hardware Timer. ![]() So it's likely not an interaction with clock select, but you have only 64 clocks to perform the interrupt and exit it. These ESP32 Hardware Timers, using Interrupt, still work even if other functions are blocking. This library enables you to use Interrupt from Hardware Timers on an Arduino, Adafruit or Sparkfun AVR board, such as Nano, UNO, Mega, Leonardo, YUN, Teensy, Feather32u4, Feather328P, Pro Micro, etc. The description below applies to both Timer/Counter1 and Timer/Counter0." According to the datasheet, "”8-bit Timer/Counter0 with PWM” on page 93 and ”16-bit Timer/Counter1 with PWM” on page 111 share the same prescaler module, but the Timer/Counters can have different prescaler settings. ![]()
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