Problems with TMR1 interruption

[Fer_taca]

I'm starting to use Flowcode and he did a basic example: turning on and off a led, using delays. The next step was the use of interruptions.

To do this, he chose to use the TMR1 to create a 1second timing. When performing the operation: oscillator of 20MHz, internal advance and prescaler of 1: 8. According to that Flowcode indicates to me that the interruption occurs every 9,5387 or what is the same 0,10483 milliseconds.

If you want to reach 1 second, within the interrupt routine I create a counter up to 10 so I should have the second of the timing plus a small error.

If I running the project simulation, I can see the output (led), associated with a pin, that changes very quickly, several times per second. However, if I change the counter to a value of 200, the output is already seen to change more or less to the second.

Is this a problem of the simulator or of someone who does not know how to do it?

Thank you very much

[kersing]

Timing in simulation is not accurate, especially when using interrupts. You will need to test on hardware for exact timing.

[Fer_taca]

Thanks for your reply.
In addition to the simulation that has become clear to me, I would like to know if the calculations I have made would be correct or not.