After, porting MTP responder to Teensy 4.0, I needed it to port it to USBHS of Teensy3.6.
So Teensy3.6 could now have MTP responder on slow primary USB or on USBHS (used for USBHost).
As I work with makefile (VSCode) it was easy to generate a own USB2_MTPDISK_SERIAL to trigger software compilation.
But before I post SW on GitHub, I would like to know how to how Arduino (boards.txt) allows me to activate 2nd USB (in addition to first)
Say USB_SERIAL and/or USB2_SERIAL, USB_MTPDISK or USB2_MTPDISK.
So Teensy3.6 could now have MTP responder on slow primary USB or on USBHS (used for USBHost).
As I work with makefile (VSCode) it was easy to generate a own USB2_MTPDISK_SERIAL to trigger software compilation.
But before I post SW on GitHub, I would like to know how to how Arduino (boards.txt) allows me to activate 2nd USB (in addition to first)
Say USB_SERIAL and/or USB2_SERIAL, USB_MTPDISK or USB2_MTPDISK.