Tool chain used for build

The following tools have been used:

Compiler:  Rowley  HCC           V1.2 Release build on Jan 15 2004 at 16:15:00
Assembler: Rowley  HAS           V1.2 Release build on Jan 15 2004 at 16:15:00
Librarian: Rowley  HAR           V1.2 Release build on Jan 15 2004 at 16:12:36
Workbench: Rowley  CrossStudio   V1.2

New features

Version 3.30a

embOS internal time handling modified to allow long delays
For 8- and 16-bit CPUs the maximum range for delays and timer periods is limited to 32767 embOS timer ticks, because time comparison ist done by integer calculation.
By recompiling sources with datatype OS_TIME defined as signed long, longer delays and timer periods up to 2147483647 ticks can be realized.
The embOS libraries of object versions for 8- and 16-bit CPUs are still delivered with the limitation to 32767 timer ticks.

Version 3.28p

New error handling for version without round robin scheduling
In debug versions of embOS, OS_Error() is called with error code OS_ERR_TASK_PRIORITY, if a task is created with a priority which is already assigned to an other task.
OS_Error() is also called with the same errorcode, if a task priority is assigned by call of OS_SetPriority() and the new priority is already assigned to an other task.
Round robin switching can be disabled by recompiling sources with OS_RR_SUPPORTED defined as 0.

Version 3.28l

OS_SignalCSemaMax()
New counting semaphore handling function which specifies a maximum count value.
This allows counting semaphores used as binary semaphores.

Version 3.28i

OS_DeleteRSema()
New resource semaphore handling function allows to delete resource semaphores during runtime.

Version 3.28h

Additional error checks in debug builds of embOS
OS_CreateRSema() now generates an error, when the addressed resource semaphore was already created before.
OS_CreateCSema() now generates an error, when the addressed counting semaphore was already created before.
OS_CreateMB() now generates an error, when the mailbox was already created before.
OS_CreateTimer() now generates an error, when the software timer was already created before.
OS_MEMF_Create() now generates an error, when the addressed fixed size memory pool was already created before.

Version 3.28g

OS_GetSuspendCnt()
New info function to examine suspension state and count of a task.

Version 3.26

OS_Terminate() modified
Tasks may be terminated anytime, regardless of task state.
All resources claimed by the terminated task are automatically released.

Version 3.22a

OS_PutMailFront() / OS_PutMailFront1()
New mailbox functions to enable LIFO behavior of mailboxes.
OS_PutMailFrontCond() / OS_PutMailFrontCond1()
New conditional mailbox functions to enable LIFO behavior of mailboxes.

Version 3.20

OS_Suspend() / OS_Resume() implemented
New functions to suspend and resume tasks unconditionally.
Fixed size memory blocks implemeted
New functions to allocate fixed size memory blocks from embOS.
Dynamic memory allocation supported by embOS
Thread safe dynamic memory allocation functions implemented.

Improvements

Version 3.28n

embOS round-robin scheduling may be disabled.
Round-robin scheduling may be disabled by recompiling sources with OS_RR_SUPPORTED defined as 0.
This will save some bytes of RAM and ROM and may make sense for small CPUs.

Version 3.28g

embOS scheduling simplified
Task activation and deactivation on "waitable objects" as mailboxes, semaphores, events, fixed size memory blocks now all use the same scheduling method.
This modification saves ROM and RAM and makes scheduler easier to understand and to maintain.
Applications which accessed internal data structures of waitable objects directly have to be modified.

Version 3.24

Stack check performance increased
Stack check now runs much faster on 32- and 16-bit target CPUs.

Program corrections

Version 3.30d

OS_MEMF_Create() corrected.
Alignment check of buffers for fixed size memory blocks did not work correctly in debug libraries of embOS.
OS_Error() was called during OS_MEMF_Create(), even though the memory pool buffers start address was correctly aligned.
This problem existed since embOS version 3.28m in all debug build libraries and is fixed with version 3.30d.

Version 3.30b

OS_Suspend() corrected.
OS_Suspend() did not work correctly, when an activated task with higher priority than the running task was suspended.
When the task with highest priority was suspended during system initialization before embOS was started, embOS crashed during the call of OS_Start(), or called the embOS error handler OS_Error() with error code OS_ERR_INV_TASK (128).
The same crash occurred, when the application was running in a critical region and a task with higher priority was activated, but not started because of the critical region, and was then suspended by a call of OS_Suspend().
This problem existed in all previous embOS versions and is fixed with version 3.30b.

Version 3.28q

Problem with suspended tasks which were on delay fixed.
If a task which was on delay was suspended, the delay timer for that task was not handled.
This might have resulted in additional longer delay when the task was resumed later.
This problem existed in all previous embOS versions and is fixed with version 3.28q.

Version 3.28p

OS_Suspend() corrected.
OS_Suspend() did not work correctly, when the current task was suspended from within an interrupt handler, or from a critical region.
The application crashed, or called the embOS error handler OS_Error() with error code OS_ERR_INV_TASK (128).
As OS_Suspend() automatically enters a critical region in debug-trace builds, OS_Suspend() also failed, when it was called to suspend the current task in debug-trace builds of embOS.
This problem existed in all previous embOS versions and is fixed with version 3.28p.

Alignment problems fixed for fixed size memeory blocks
Some CPUs, mainly the 32bit RISC types, require aligned buffer start addresses for fixed size memory pools.
The debug version of embOS now checks alignment of buffer start address and data blocks in the buffer. If data blocks and buffer start address is not aligned, an error is generated and embOS error handler is called during creation of a fixed size memory pool.
This problem existed in all previous embOS versions and is fixed with version 3.28m.

Version 3.28l

OS_MEMF_Free() added
The function OS_MEMF_Free() was not included in embOS libraries, but was documented in embOS users manual and was also declared in RTOS.h.
This problem existed in all previous embOS versions and is fixed with version 3.28l.

Version 3.28k

OS_MEMF_IsInPool() corrected
OS_MEMF_IsInPool() failed, if a pointer was checked which pointed to the first address after the memory pool. This pointer was reported as belonging to the pool.
This problem existed in all previous embOS versions and is fixed with version 3.28g.

Version 3.28g

OS_WakeTask() for trace build corrected
OS_WakeTask() in trace build disabled task switches.
This problem existed since version 3.24 and is fixed with version 3.28g.
OS_GetMailTimed() / mailbox handling corrected
During call of OS_GetMailTimed, interrupts were re-enabled too early. If a mail was just put into a mailbox and the timeout occurred at the same time, a mailbox internal control variables which managed waiting tasks was set to a wrong value.
This resulted in wrong mailbox handling and caused task waiting for mail kept suspended, even though, mail was available. This problem existed in all previous versions of embOS and is fixed with version 3.28g.

Version 3.26a

OS_MEMF_Release() corrected
OS_MEMF_Release() might have failed according to absolute address of memory block.
The problem occurred because address calculation was done with 16bit interger value.
Calculation was modified to use 32bit values to fix the problem.

Version 3.20c

OS_GetMailTimed() corrected
OS_GetMailTimed() did not retrieve a mail after 256 calls, the waiting task remained suspended. Corrected with version 3.20c of embOS.
This problem exists in all previous embOS versions and is fixed with version 3.20c.

Known problems/limitations

Version 3.30d

None.

Release history

Version	Release date	Short explanation
V3.30d	11. Jul 2006	Updated, corrected embOS version V3.30d
V3.20f	30. Apr 2003	Initial release for MSP430 using "Rowley CrossStudio 1.2 for MSP 430"

Miscellaneous

This document was first released with version 3.20f of the software.
Software released earlier is documented internally. This information is available at request.