FX3 GPIF - Intr_CPU recovery time / frequency

[FaFi_4159091]

Hello,

I have a very simple callback (toggles a single pin via direct register access) registered to the Intr_CPU function in GPIF. My GPIF design calls Intr_CPU every 15 us and the pin is toggled almost immediately, which indicates a acceptable latency. However, only every thirtd interrupt is executed, as if there is some recovery time after the last intr_cpu before the next can be called. The callback function takes definitely a lot less than 15 us to return.

Is there a way around this?

[Rashi_Vatsa]

Hello Fabian,

- Can you confirm how do you calculate the 15 us between two GPIF interrupts.

- Can you share the traces (GPIO toggling)

- How are you getting back to the state machine? Can you share the firmware part which contains this implementation

Regards,

Rashi

[FaFi_4159091 · Accepted solution]

Hello Rashi,

thanks for your answer. I measured the 15us by tracking a control signal with a oscilloscope.

However, I would mark this thread as resolved, since I've found a solution: I created an infinite loop at the end of my readout-sequence, which spams interrupts every 1 us until the firmware signals, the interrupt is handled.