I don’t actually have a picocalc yet so I may be misinterpreting things. However, looking at the circuit diagram it seems there are two serial ports exposed, one on the Pico itself and one on the MCU, one of which is always driven by the CH340C through the bilateral switch. Neither have flow control. If I wanted RS-232 serial IO with CTS/RTS that will not be usurped by the system unexpectedly, what is the best way to do this? Ideally the port will be available in Basic with flow control (which I assume may require firmware changes but that’s OK)
The perfect solution for me would be to add a DB-9 to the case with a level shifter provided the appropriate signals are available.
Here are the ports exposed on the side of the PicoCalc. It looks like there are two serial ports (TX/RX pairs) Perhaps you could do something with those.
Indeed, those are the ports that connect to each processor (MCU and PICO) and which may be routed to the USBC via a CH340 and internal switches. Neither of these have flow control and I am unsure under what conditions the USB is connected.
