Connection
Idle
Device Recovery
Use CTRL-AP mass erase to recover an APPROTECT-locked device. All flash and UICR will be erased.
Firmware Image
No image loaded
Debug (Cortex-M)
Halt/resume/step the Cortex-M core via DHCSR. Target must be connected.
Memory Read
UICR (nRF52)
User Information Configuration Registers. Read-only unless device is unlocked and NVMC write-enabled.
RTT (Real-Time Transfer)
Searches target RAM for SEGGER RTT control block, then polls ring buffer. Target must be running firmware with RTT initialized.
UART Passthrough
Routes probe UART to target TX/RX via DAP_UART_* (CMSIS-DAP v2.1). Probe must report capability bit 7 (UART Port).
SWO / ITM Trace
Serial Wire Output trace via DAP_SWO_* (CMSIS-DAP v1.3). Probe must report capability bit 2 (SWO UART) or bit 3 (SWO Manchester).