And now it responds to characters we type! My guess is that now that we get Rx interrupts from the serial port, things have come alive.
I put printf into the interrupt handlers, first for the timer, then for the serial port, and confirm that both are receiving interrupts as they should (and as they did when running on the H3).
The A53 is at least 20 percent faster at the same clock, which is significant, yet not really a big deal.
What is interesting about the H5 and H3 is that the peripherals in the chip (timers, uart, network, etc.) are identical. The same IO addresses, the same interrupts assignments, and so on. This means that drivers and code that I wrote for the H3 will work without change on the H5.
Given that the H3 has become more or less the flagship port of Kyu (next to the original BBB), it should be a quick and easy path to getting Kyu running nicely on the H5.
Tom's electronics pages / tom@mmto.org