I hope this information is helpful for your exploration of high-speed level conversion with GPIO. Thank you very much! I tested performance of GPIO from inside kernel (and thus not userspace). Using in-kernel linux GPIO API gpiod_set_value (e.g. GPIO consumer interface). It gives about 4 million ca...

Dear @Crocodile, thank you very much for your detailed answer! I wrote a kernel module and got to use Libgpio and also directly gpio_chip->set(...) function. My problem is that a call to such methods for setting GPIO pin takes about 500 nanoseconds. But by the way I have to write a protocol that hav...

I tryed wiki GPIO using sysfs https://wiki.luckfox.com/Luckfox-Pico/Luckfox-Pico-GPIO and it is absolutely slow. For example, I need to maintain high signal for 700ns, but calling write/fwrite is about 20000ns. So I failed to implement the desired GPIO protocol. Question 1. Is there a documented way...