Thanks for the suggestion, I think I'll probably experiment with that as a quad UART PPP multilink, as a quicker/easier solution, and see how it behaves. I hadn't caught on to the UARTs being potentially capable of Mbaud rates. I'm curious about 3Mbaud being possible, as that seems to exceed the ARM documentation for the PL011 in the Pi4B, unless I'm looking at the wrong ARM docs. I can see where the 3Mbaud comes from, in terms of taking the ~48MHz UART clock and dividing by 16, per the BCM2711 docs, it's just not consistent with the PL011 docs. The PrimeCell UART (PL011) Technical Reference Manual r1p5 states that the maximum baud rate is "921600 bps, in UART mode". I'm guessing it could be like the old Acorn RS423 ports which had an official spec which was lower than the maximum configurable rate, and you could push them beyond spec with a bit of luck and increased potential for bit errors. I don't necessarily need all that much bandwidth for cluster heartbeat / management purposes, but am curious to see what can be achieved between a pair of Pi 4Bs.
I'm guessing for safety, that I should be going from Pi X, to a 200R DIP resistor pack, to Pi Y; for a ~16mA current limit (@3.3V) to safely protect the GPIO pins on the Pis from misconfiguration?
I'm guessing for safety, that I should be going from Pi X, to a 200R DIP resistor pack, to Pi Y; for a ~16mA current limit (@3.3V) to safely protect the GPIO pins on the Pis from misconfiguration?
Statistics: Posted by Murph9000 — Tue Aug 27, 2024 2:16 am