Scan for connected debug probes and show what hardware is attached. Use this first if you don't know what device is connected.

Set the target device name at runtime. Required before any debugging commands will work. Examples: 'nRF52840_XXAA', 'nRF5340_xxAA_APP', 'STM32F407VG', 'STM32L476RG'.

One-call setup: starts GDB server via SEGGER J-Link, connects RTT (if supported), waits for initial output. This is the recommended first tool to call. If no device is configured, use list_devices and set_device first.

Capture complete device state: CPU registers (compact), fault status, recent RTT output, and stack dump.

Auto-read and decode ARM Cortex-M fault registers (CFSR, HFSR, MMFAR, BFAR), exception stack frame, and recent errors.

Get connected device info via SEGGER J-Link. Returns probe type, target CPU, and compact register summary.

Halt the target CPU

Resume the target CPU

Reset the target device

Step one CPU instruction

Read memory from the target. Returns clean hex dump.

Write a 32-bit value to memory

Read all CPU registers (compact format, FP only if non-zero).

Read a specific CPU register by name

Flash firmware to the target device

Erase target flash memory

Set a hardware breakpoint

Clear all breakpoints

Start SEGGER J-Link GDB server

Stop SEGGER J-Link GDB server and disconnect RTT

Get GDB server, RTT, and telnet proxy status

Connect a GDB client to the running GDB server. Enables source-level debugging: backtraces, variable inspection, conditional breakpoints, stepping by source line. Optionally load an ELF file for symbol info.

Send any GDB command and get the response. For execution commands (continue, step, next, finish, until), blocks until the target stops or times out. If the target doesn't stop, use gdb_wait to poll. Examples: 'bt' (backtrace), 'info threads', 'print myVar', 'break main', 'continue', 'next', 'step', 'finish', 'info registers', 'x/10xw 0x20000000'

Poll for target stop after a continue/step that timed out. Returns the stop reason (breakpoint hit, signal, finished stepping, etc.) when the target halts.

Load an ELF file into GDB. By default loads symbols only (for source-level debugging: backtraces with file:line, variable names). Set flash=true to also program it onto the target.

Get a stack backtrace. With debug symbols loaded, shows function names, file paths, and line numbers.

Disconnect the GDB client (does not stop the GDB server)

Connect to RTT

Disconnect from RTT

Read recent RTT log lines (clean, parsed Zephyr format)

Search/filter RTT logs by level, module, or regex

Send data to device via RTT down-channel

Clear RTT buffer

Start TCP proxy for Trice/Pigweed detokenizer

Stop telnet proxy

Get telnet proxy status

Read raw data from telnet proxy buffer

Execute raw SEGGER J-Link commands

Get current probe and server configuration