Release notes for embOS Version 3.32o for National Semiconductor CR16C and IAR compiler

  1. Tool chain used for build
  2. New features
  3. Improvements
  4. Program corrections
  5. Known problems/limitations
  6. Release history
  7. Miscellaneous

Tool chain used for build

The following tools have been used:

Compiler:  IAR ICCCR16C  V2.11a
Assembler: IAR ACR16C    V2.11a
Librarian: IAR XAR       V1.03L
Workbench: IAR IARIDE    V4.6B

New features

Version 3.32m

  1. OS_TimerEx, Extended timer implemented
    Extended timers are software timers which call a user defined callback function when the timer expires.
    In comparison to normal embOS timers, a parameter is passed to the timer callback function.
    The parameter value is initialized during timer creation.

Version 3.32l

    OS_EnterIntStack() and OS_LeaveIntStack are implemented to safe space on task stack.

Version 3.32j

    First version. None.


Version 3.32o

  1. Automatic call of OS_INIT_SYS_LOCKS() removed.
    During initialization of embOS, OS_INIT_SYS_LOCK() is not called automatically.
    As most of the applications do not need thread safe system libraries, an automatic activation of syslocks causes unwanted overhead.
    If supported and required, the user may call OS_INIT_SYS_LOCKS() from his own application after normal initialization of embOS.

Program corrections

Version 3.32o

  1. OS_Unuse() corrected
    OS_Unuse() must not be called from a task that does not claim the resource semaphore.
    According to the documentation, the debug build of embOS should generate a call to OS_Error() if this fault happens.
    All previous versions of embOS did not call OS_Error(). Now, OS_Error() will be called in that situation with error code 156: OS_ERR_RESOURCE_OWNER().
  2. Enter-/LeaveIntStack corrected
    A word access to a byte variable caused errors

Version 3.32l1

  1. Stack switch corrected
    Interrupts must be disabled while counter for default stack is changed and stackpointer is set to default stack.

Version 3.32l

  1. OS_EVENT_Delete() corrected
    OS_EVENT_Delete() did not work correctly. OS_LeaveRegion() was called inside the function without calling OS_EnterRegion() bfore.
    In debug builds of embOS, the error handler OS_Error() was called with error 151 (OS_ERR_LEAVEREGION_BEFORE_ENTERREGION).
    In release builds the system was blocked because the underflow of region count inhibts all further task switches, or system crashes, because incrementing the region count the next time allows task switches instead of blocking them. The problem existed in all previous versions and is fixed with version 3.32l.
  2. Round-robin task switching corrected.
    Round robin task switching did not work correctly in previous version. A task which was blocked for some reason could be activated. The system crashed during task switch.
    The problem existed since version 3.32j and is fixed with version 3.32l.

Version 3.32k

  1. Handler function _OS_OnTx() for serial communication to embOSView corrected.
    The transmission handler for communication with embOSView might have sent incorrect data to embOSView, because internal control state was updated after sending the data.
    The problem occurred on a new embOS port for a specific CPU only and is fixed with version 3.32k.

Version 3.32j


Known problems/limitations

Version 3.32j


Release history

Version Release date Short explanation
V3.32o 30. Apr 2007 OS_Unuse() error handling improved.
Enter-/LeaveIntStack corrected.
V3.32l1 02. Apr 2007 Stack switch corrected.
V3.32l 28. Mar 2007 Round robin switching corrected.
V3.32j 01. Mar 2007 First version with release history


This document was first released with version 3.32j of the software.
Software released earlier is documented internally. This information is available at request.

Copyright 2001-2007 SEGGER Microcontroller Systeme GmbH. All rights reserved.
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