I am currently developping an application on a Raspberry pi (current HW is 3B+) which has to discuss with a FPGA component à 5MBauds through an UART connexion. Default max value on ttyAMA0 is 3MBauds (and I checked with a scope, the period is 333ns as expected). By changing the /boot/config.txt and adding the init_uart_clock. Doing that, I am able to increase the max UART speed to 4MBauds but I failed to increase the baud rate to 5MBauds.
So I am asking myself some questions:
Has anybody already succeed to go to such baudrate on an UART with the 3B+ on /dev/ttyAMA0 ?
Would it be better on /dev/ttyS0 ? As my actual application is orriented on performance and not on power consumtion, I can add a fan and fix the clock value to use the S0 with high clockrate ?