read.me

比较老的ucos最初的版本

                   uCOS, The Real Time Kernel
                           Revision A

By  : Jean J. Labrosse
Date: June 10, 1992


     Three   discrepencies  (bugs)  were  recently  brought to my
attention.  The 'bugs' have to do with boundary conditions. Files
UCOS.C  and  UCOS186C.C  were  corrected   accordingly  (see  the
comments).  Also, OSTaskCreate() now returns an error code  which
indicates  either OS_PRIO_EXIST (the  priority  already exist) or
OS_NO_ERR (the task was successfully created).

     For your convenience, I have combined the code for both  the
May  1992  and June 1992 issues of  Embedded  System  Programming
Magazine.   The  code  assumes that you  are  using  the  Borland
International C++ Version 3.0.

     To  compile  the  two  test  cases, you  would start the IDE
(Integrated  Development  Environment)  and open  either  project
TEST1.PRJ  or  project TEST2.PRJ.  However, before  you  compile,
you  need  to  create  an  OBJ  subdirectory  from  your  current
directory.  Also,  my Borland  compiler  is located in the C:\CPP
directory.  If  your  compiler is in a  different  directory, you
will need to edit the  DIRECTORY  entries  IDE.  To  compile  the
code, simply press the F9 key.   Code generation  assumes maximum
speed optimization.

     I have included TEST1.EXE and TEST2.EXE which allows you  to
run the examples directly.

     I am currently working on a book version of uCOS.  The  book
will  describe  the internal working of this  kernel  in  greater
detail.  The magazine article version had few comments because of
a 55 character limit imposed by most magazines.  The code in  the
book  version will be fully commented.  I also made a  number  of
changes to the structure:

     - uCOS is now easier to setup
     - The code was optimized
     - Interrupts are disabled for less than 400 bus cycles
     - A task can now delete another task (or itself)
     - A task can change another task's priority
     - uCOS now provides a real time clock
     - OSTimeTick() is faster (11000 vs 15000 bus cycles max.)

     The  book  is schedule to be available this  fall  from  R&D
Publications; the publisher of "The C Users Journal" and will  be
advertised in this magazine.

     I  would like to thank Mr Tyler Sperry of  Embedded  Systems
Programming  Magazine for  publishing  uCOS and Mr Bob Shafer for
pointing out the bugs in uCOS.  I hope you will find uCOS useful.

     Sincerely,


     Jean