* using WITH_FPC:
* activate basic usart
* no double buffer for now, no interrupt
* usart_dataavailable/usart_readbuffer/usart_writebuffer, to demo it:
* pm3 client over USB, minicom over usart
* analyse a d 414243
* using WITH_FPC_HOST:
* it implies WITH_FPC as it's based on it
* control pm3 with client over usart
* EXPERIMENTAL! still some frame desync issues
* you can connect both from usart & USB with two pm3 clients
* actually you *have* to connect USB for the moment because
it's used to send debug messages about buggy usart... See Dbprintf_usb below
* "sessions": msgs are directed to the latest client to have sent a cmd
* Dbprintf_usb macro to send msgs to USB client to help debugging usart...
* We now have an option to run client at different speed as usart is 115200:
client/proxmark3 /dev/ttyUSB0 -b 115200
* Consequently, argc,argv handling is a bit revamped, it was so messy...
* USB and flashing are still at 460800, don't try flashing over usart yet ^^
