Atmega328 timer1 reload interrupt

Hello,
it looks like the timer reload isr of timer1 (TIMER1_CAPT_vect) doesn't execute in SimulIDE.
The attached sketch outputs a variable duty cycle pwm (PWM frequency 62500 Hz) on pin 9 of an arduino uno. It works in real hardware. The output, filtered by a simple RC filter,  becomes a 244 Hz sine wave.
But in SimulIDE the output is just a 62.5 kHz square wave with 50% duty cycle.

I tried SimulIDE 1.1.0-RC0 rev. 1908 and rev. 2036

Hi.

Not sure if I understood your code correctly but as far as I know TIMER1_CAPT_vect if for Input Capture unit.

Hi,
thanks for your quick response.

In Mode 14 (Fast PWM) the ICF1 flag is set when the counter reaches the value of ICR1, see p. 102 of the datasheet.
So the Input Capture Interrupt can be used to set a new value for OCR1A to change the duty cycle.

With a real Arduino Uno the output at PIN9 looks something like this:


But in SimulIDE it looks something like this:


I forgot one typecast in the arduino sketch of the first post, attached is a corrected version.

In Mode 14 (Fast PWM) the ICF1 flag is set when the counter reaches the value of ICR1, see p. 102 of the datasheet.
So the Input Capture Interrupt can be used to set a new value for OCR1A to change the duty cycle.

Ok thanks for the explanation.
As far as I can remember this is not implemented, I will have a look.

With

Code:

TIMSK1 |= (1<<TOIE1);
ISR(TIMER1_OVF_vect) { ...

it works as expected.

Nice.
I still have to implement the Input Capture Interrupt at Output Compare match in fast mode.

And I guess it does not work the same, the proper moment to update OCR value is as you did.

I think this issue is solved at Rev 2048.

Keep an eye in this discussion for new executables:
https://simulide.forumotion.com/t550-simulide-trunk-tester-builds#2961