QUERY · ISSUE
Add support for dual usb serial on the Pico.
enhancement
The pico has the hardware to support for enumerating as multiple usb serial ports on the host computer. This is proven by the fact that CircuitPython exposes the ability to do so.
CANDIDATE · ISSUE
Suggested feature: add a second USB serial port for remote control features
I have a fork of the firmware for the CANPico boards and have added a second USB serial port for use by MIN (a reliable serial transport protocol) to send and receive remote control commands from a host (in my case, pushing CAN frames received to a host to see in Wireshark). It's a lot more robust than trying to multiplex the REPL serial port into raw mode.
I hardwired the second port by bumping CFG_TUD_CDC to 2 in tusb_config.h and the table usbd_desc_cfg in tusb_port.c.