2022-10-20 07:30 PM
Hello,
I'm using STM32F303RB and 72MHz Clock is being used by using PLL
I have a few questions
Q1) What is the maximum operating speed of GPIO output? (8MHz or 72Mhz)
Q2) Is there PORT with bit banding?
Thank for all your supoort.
Best regrads.
JH moon.
2022-10-20 07:55 PM
Check the datasheet gpio speed bit registers or similar. Not ref manual. I would say 48 MHz is safe if pin load is right. Going to qspi or octospi external memories demand high speed anyway. Even max SPI speed hints min IO toggle speed.
2022-10-20 11:41 PM
i made test with F303 , at 72MHz; for building a "mini-DSO" ...
HAL uses some clocks , about 260ns for 1x lo-hi-pulse,
but when writing direct to port , with optimizer -Ofast (speed) :
meas. about 15ns (ideal 13,9ns = 1 tick 72MHz); so really 1 clock tick.