Arduino R4 Wifi - debuging not working / available

Development Tools IDE 2.x
1

Hi,

When trying to use debugging, i get the following error:

Waiting for gdb server to start...[2025-07-29T11:30:16.917Z] SERVER CONSOLE DEBUG: onBackendConnect: gdb-server session connected. You can switch to "DEBUG CONSOLE" to see GDB interactions.
"C:\\Users\\rwhiffin\\AppData\\Local\\Arduino15\\packages\\arduino\\tools\\openocd\\0.11.0-arduino2/bin/openocd" -c "gdb_port 50000" -c "tcl_port 50001" -c "telnet_port 50002" -s "u:\\Arduino\\ArduinoR4_D13_D6_D5_Main" -f "C:/Users/rwhiffin/AppData/Local/Programs/Arduino IDE/resources/app/plugins/cortex-debug/extension/support/openocd-helpers.tcl" -f interface/{programmer.protocol}.cfg -f {programmer.transport_script} -f "C:\\Users\\rwhiffin\\AppData\\Local\\Arduino15\\packages\\arduino\\hardware\\renesas_uno\\1.5.0/debugger/R7FA4M1AB.cfg"
Open On-Chip Debugger 0.11.0+dev-gab95bac57-dirty (2021-05-11-10:45)
Licensed under GNU GPL v2
For bug reports, read
        http://openocd.org/doc/doxygen/bugs.html
CDRTOSConfigure
embedded:startup.tcl:26: Error: Can't find interface/{programmer.protocol}.cfg
in procedure 'script' 
at file "embedded:startup.tcl", line 26
[2025-07-29T11:30:17.081Z] SERVER CONSOLE DEBUG: onBackendConnect: gdb-server session closed
GDB server session ended. This terminal will be reused, waiting for next session to start.

Any suggestion how to resolve?

Regards,
Rowland

2

Hi @rowlandwhiffin. Select Tools > Programmer > ARM CMSIS-DAP compatible from the Arduino IDE menus, then try starting the debugger again

Explanation

Although we traditionally used this Tools > Programmer menu to select an ISP programmer to use for a firmware flashing operation ("Burn Bootloader" or "Upload Using Programmer"), the menu now has an additional use for configuring the interface between the Arduino board and Arduino IDE's debugger.

The UNO R4 WiFi has an on-board debug probe. This debug probe uses the CMSIS-DAP protocol, so the appropriate item to select from Arduino IDE's Tools > Programmer is "ARM CMSIS-DAP compatible".