readme.txt

ppc860的ucos part

file: readme.txt V1.00

This readme.txt file is associated with the BSE PowerPC port of UCOS-II
kernel.

Usage of this port assumes an intermediate level or higher knowledge of
and familiarity with the 32-bit PowerPC programming environment.

Installation instructions:
1) Copy ppc8xx.zip to the directory /software/ucos-ii
2) Unzip preserving path information, e.g.'unzip -d ppc8xx.zip'

These distribution files include the essential files necessary to
implement the UCOS-II kernel on a PowerPC target.  The port has been
demonstrated to work on an MPC8xxFADS and an MBX860.  The code has
been tested on UCOS-II, V2.00, and UCOS-II, V2.03, with the Diab C
Compiler Suite, V4.3b. This code is incompatible with UCOS, V1.xx.
This code is also incompatible with PowerPC devices which implement
the floating-point model.

This distribution contains ONLY the PowerPC port code.  It is
expected that the user will have acquired the code for the UCOS-II
kernel and the associated manual from Jean J. Labrosse, Weston, FL
[e-mail] . See http://www.ucos-ii.com for details.

In addition, the User must provide user target specific board
initialization (startup.s) for their specific target environment.
In the event the startup initialization is provided by the debugger
startup script, then set .org to 0x4000 in bsecrt0.s, for example,
modify the entry point to _start in bsecrt0.s during the build process,
and load and run it with the debugger.

This implementation uses the PowerPC Decrementer Exception for the
timer tick operation, and uses the PowerPC System Call Exception
for the Context Switch operation.  They are located at vector offsets
0x???00900 and 0x???00C00 respectively, where ??? is "000" or "FFF"
depending on the state of the MSR[IP] field.  The code as written
assumes that MSR[IP] == 0b, and thus ??? == 000.

The example exception handler installers in bsetest.c are machine
language, but they suffice for demonstration. In a real implementation,
the user may assemble/link "b DECIntr" and "b OSCtxSw" instructions to
 the proper origins in the exception table at compile time. This can
be done in startup.s, for example. Regardless of the method chosen to
install them, they must be installed before starting UCOS-II. 

A model makefile is provided, but it will have to be modified for the user
environment.

Files:

bsetest.c:
Provides some trivial demonstration code to show that the OS is
running and multi-tasking.

bseppcc.c:
Contains the PowerPC specific C language code for UCOS-II

bseppca.s:
Contains the PowerPC specific Assembly language code for UCOS-II

include.h
This file references by inclusion two files: ucos_ii.h, and bseppc.h

ucos_ii.h:
This file is unmodified from the UCOS-II distribution code.  See the
UCOS-II distribution for this file.

bseppc.h:
This file contains PowerPC specific code and UCOS-II kernel configuration
#define's and typedef's.

bsecrt0.s:
This model C RunTime initialization code file (bsecrt0.s) is included.
It will work with the Diab Compiler Suite, but it will likely have to
be modified somewhat to work with another build environment, e.g., GNU.

bsetest.dld:
This is a Diab linker command file for the MPC8xxFADS target.

makefile:
This is a GNU make compatible makefile for the Diab Compiler Suite
environment. It references bsestart.s which is the startup file that
 will have to be provided by the user.  The makefile also assumes
that all the UCOS-II *.o files are in a library named ucos-ii.a found
at /software/ucos-ii/lib. If the user wants to link in ucos-ii.o, or
the individual os_???.o files directly, the makefile will need to be
changed accordingly.  However, note that the UCOS-II kernel MUST be built
with the same or an identical "includes.h"  as that used to build the
target specific modules. Note particularly that the kernel modules must
be built using the configuration found in  bseppc.h, however the user
chooses to implement it. The way I chose to do this was to put these
two include files in an include directory at /software/ucos-ii/include,
with a local "includes.h" file for both the kernel library directory
and the target specific directory, and the  makefile reflects this.
Modify to suit your own environment.

Author: Harry E. Barnett
Barnett Systems Engineering
[e-mail] http://www.hbbse.com