Debugger Hints and Tips

When using Visual Studio to debug wRTOS applications, note the following hints and tips.

Debug Behavior

• If you are unable to debug an RTSS application, make sure the MaxRT wRTOS Debugger is the selected debugger.
• While debugging, only the process being debugged is frozen when a breakpoint is hit. All other Real-time processes along with the Subsystem continue to run.
• In the event that no debugger is specified in Visual Studio, or you do not see the MaxRT wRTOS Debugger in the drop-down after you create a project, try the following:
• Make sure the files wRTOS.Targets, wRTOSBaseDm.xaml, and wRTOSRemoteBaseDm.xaml are installed in the following directory:

• %wRTOSCommon%\DebuggerExtensions\

• Verify that the files wRTOSBaseDm.xaml and wRTOSRemoteBaseDm.xaml exist in the same directory

If the wRTOSBaseDm.xaml and wRTOSRemoteBaseDm.xaml files exist and you still do not see the MaxRT wRTOS Debugger, try the following:

• Unload the project, right-click on the project and edit the project file.
• Make sure the following lines exist near the bottom of the project file:

</ItemDefinitionGroup>

<Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />

<Import Project="$(wRTOSCommon)\DebuggerExtensions\wRTOS.targets"

Condition="exists('$(wRTOSCommon)\DebuggerExtensions\wRTOS.targets')" />

• If you receive an error message when you start debugging, make sure:
• The Subsystem is running. The Subsystem must be running before you can start a Visual Studio debugging session.
• The RtssDebug x64 configuration is selected.
• In the Visual Studio Extensions and Updates dialog (Tools > Extensions and Updates), make sure the MaxRT wRTOS Debugger is listed as an extension, and that it is both enabled and installed.
• The MaxRT wRTOS Debugger does not allow disassembly/single step of wRTOS system calls (for operational security such as atomic sections).
• The MaxRT wRTOS Debugger does not display the Process ID (PID) for RTSS processes being debugged. A GUID is displayed instead. This is expected behavior when Visual Studio is used to debug a non-Windows process. The PID is displayed in the Output window.
• Deterministic behavior does not exist while using the MaxRT wRTOS Debugger. As a result, wRTOS users should not depend on the execution order of multiple RTSS applications being debugged by multiple MaxRT wRTOS Debugger instances.
• The RTSS thread priority shown in the Visual Studio Debugger Threads window will display Unknown if the real-time priority value does not correspond to a Windows thread priority. RTSS thread priority values range from 0 to 127 and Windows thread priorities range from -15 to 15. If a real-time priority value matches a Windows value, the text displayed in the debugger Threads window will not be meaningful.
• You can step into the functions exported by RTDLL but cannot step into or set a break pointer in DllMain function.
• You must close the Visual Studio debugging session before stopping the wRTOS Subsystem.
• Breakpoints are not allowed in an Interrupt Service Routine (ISR).
• The Visual Studio Registers window displays registers during a debug session. Visual Studio 2022 and Visual Studio 2019 currently do not display CET - Shadow Stack Pointer registers.