Today we worked on implementing a debugging UART mode for the Bus Pirate v4. To talk to your computer the Bus Pirate v4 uses a software USB stack coded in the firmware. While this gives us some advantages, it has a disadvantage of hanging if in-circuit debugging is needed. The USB simply fails and no communication with the PC is possible from that point on.
To tackle this problem we are adding a special debugging mode to the Bus Pirate v4 firmware, which will transfer the communication protocol to UART accessible through the AUX1 and AUX2 pins. As a further development we might add this mode as a selectable menu option, giving you the possibility to connect to the Bus Pirate over USB, or through UART.