During the program development phase, the Debug Version of RTKernel-32 should be used by all means. It contains additional code to recognize a number of error conditions. If an error occurs, the program is aborted with an error message. Moreover, the Debug Version can determine at which source code position a task is suspended. Also, it can calculate the CPU time usage of tasks and interrupts. To locate persistent bugs, it features the real-time Kernel Tracer, which can also be used by the application.

Naturally, the Debug Version will not perform as fast as RTKernel-32's Standard Version. The only reason not to use the Debug Version during the testing phase could be the higher interrupt latency. To change the version used, a program need not be recompiled; relinking is sufficient. To use the Debug Version, link library Rtk32.lib (or Rtk32mp.lib for the multiprocessor kernel). The Standard Version is selected by linking Rtk32s.lib or Rtk32mps.lib instead.

In the Debug Version, function RTKernelInit will display the message

RTKernel-32 Debug Version

to inform the programmer that the Debug Version is being used.

The Debug Version's exit function will display the message

RTKernel-32 exit function

If this message is not displayed, execution of the exit function has been aborted, RTKernel-32 was unable to restore the interrupt vectors, and the system may be in an unstable state.

During execution of an RTKernel-32 application, the Debug Version checks the following conditions:

It is checked whether every semaphore and mailbox used has been initialized and has not been corrupted.
It is checked whether every task handle passed to RTKernel-32 references an existing task (except for function RTKGetTaskState).
Every time RTKernel-32 is called, the stack of the active task or interrupt handler is checked for overflow. This behavior can be suppressed by resetting flag RF_STACKCHECKS in RTKConfig.Flags.
In a blocking task switch, it is checked whether the task switch was triggered by an interrupt handler.
Internal RTKernel-32 data structures are checked for consistency.

If a check fails, the program is aborted with an error message. All error messages are listed in section Error and Information Messages.

In addition to run-time checks, the Debug Version also writes kernel tracer entries into the trace buffer for every task state change and all semaphore, mailbox, and spinlock operations. Depending on RTKConfig flags, it can accumulate the CPU time consumed by tasks, interrupts handlers, and spinlock (see functions RTKTaskInfo, RTKIRQInfo, and RTKGetSpinlockTime).

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