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

Tool chain used for build

The following tools have been used:

Compiler:  IAR ICCH8  V1.53H/W32
Assembler: IAR AH8    V1.41A/W32
Librarian: IAR XLIB   V3.27I/386
Workbench: IAR EW231  V2.31b

Performance

1. Task switch time
   Large memory model: 25.5 us = 357 cycles
2. Interrupt latency for Fast interrupt
   Large memory model: max. 1 us = 14 cycles

Absolute timings are based on an H8S 2239 running at 14.75 MHz with release build library

New features

Version 3.22

1. H8S CPU supported
   Since version 3.22, embOS for H8/H8S also supports H8S CPUs
2. OS_PutMailFront() / OS_PutMailFront1
   New mailbox functions to enable LIFO behavior of mailboxes.
3. OS_PutMailFrontCond() / OS_PutMailFrontCond1()
   New conditional mailbox functions to enable LIFO behavior of mailboxes.

Version 3.20

1. Fast interrupts supported
   Interrupts with high priority are never disabled by embOS.
2. OS_Suspend() / OS_Resume() implemented
   New functions to suspend and resume tasks unconditionally.
3. Fixed size memory blocks inplemented
   New functions to allocate fixed size memory blocks from embOS.
4. Dynamic memory allocation supported by embOS
   Thread safe dynamic memory allocation functions implemented.

Improvements

NONE

Program corrections

Version 3.22

1. Task context saving / restauration corrected
   Version 3.20 of embOS for H8 could lock task switches,
   when a task was terminated by OS_Terminate()
   and the same task control structure was reused.
   This problem is corrected with version 3.22

Known problems / Limitations

Version 3.22

1. embOS on H8S CPUs runs with interrupt MODE 2 only.
   Interrupt handler using embOS functions are limited to priorities 1 to 5.

Version 3.20

1. Version 3.20 was built for H8 CPUs only.
   embOS on H8 CPUs runs with interrupt MODE 1 only.
   Interrupt handler using embOS functions are limited to lowest priority.

Release history

Miscellaneous

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