That's not strictly true.How are you working around the fact that you only have 12 statemachines?
I think the maximum you can get is 8 UARTs. Two hardware and 6 PIO. You need one for rx and one for tx.
If you can accept only one PIO controlled TX signal being active at any time then you have 11 State Machines available to do asynchronous receives in parallel, giving a grand total of 13 UART.
In many cases, perhaps almost all, not transmitting in parallel won't cause a problem.
You can also drop a UART and have 2 State Machines controlling TX signals which would only block once both were in use. And so on down to having 8 UART where all can transmit in parallel.
Code:
.--------.-------.----------------.---------------------. | UART | RX TX | TX in parallel | Potentially blocked | |--------|-------|----------------|---------------------| | 8 | 6 6 | 8 | None | | 9 | 7 5 | 7 | 2 | | 10 | 8 4 | 6 | 4 | | 11 | 9 3 | 5 | 6 | | 12 | 10 2 | 4 | 8 | | 13 | 11 1 | 3 | 10 | `--------^-------^----------------^---------------------'Statistics: Posted by hippy — Tue Nov 04, 2025 12:37 am