3.6 Connecting External Debuggers
Even though there is an on-board debugger, external debuggers can be connected directly to the ATtiny1607 Curiosity Nano to program/debug the ATtiny1607. The on-board debugger keeps all the pins connected to the ATtiny1607 and board edge in tri-state when not actively used. Therefore, the on-board debugger will not interfere with any external debug tools.
CAUTION: To avoid contention
between the external debugger and the on-board debugger, do not start any
programming/debug operation with the on-board debugger through MPLAB® X IDE or Microchip Studio or mass storage
programming while the external tool is active.