FreeModbus Coldfire MC523x PORT with lwIP
REQUIREMENTS
============
The FreeModbus/lwIP port requires are port of the lwIP TCP/IP stack for
the target platform. This port includes a suitable Ethernet driver for
lwIP as well as a FreeRTOS port.
The FreeModbus part itself does NOT depend on FreeRTOS or the Coldfire
ethernet controller and can therefore be used for creating other ports.
The development environment used is based on the GNU C Compiler for
a m68k-elf target as well as the insight debugger with some patches for
the BDM interface[1]. GDB startup and linker scripts are supplied with
the demo for the M5235BCC evaluation kit from Freescale.
[1] ... BDM tools: http://sourceforge.net/projects/bdm/
USAGE
=====
A makefile is supplied with the demo application and a binary can be
produced by calling 'make all'. A special target 'debug' is provided
which executes the insight debugger. At the insight debugger prompt
one should select the appropriate target interface (either BDM/Direct
or BDM/TCP) and should download the application to the development
board. It is important that the GDB script setup-and-load is executed
prior to downloading to initialize the SDRAM. After downloading one
should call the GDB function 'execute' and the PC is set to the start
of the executable. Execution can be started by typing 'continue' at
the Insight console interface.
In addition it is possible to download the software to the flash. This can
be done by calling 'make flash-erase' and 'make flash-programm'.
By default the port using the following settings:
IP Address : 10.0.10.2
Netmask : 255.255.255.0
Gateway : 10.0.10.1
Modbus TCP Port : 502
COMMON PROBLEMS
===============
Most of the problems have their origin in the startup scripts. The
following list should serve as a checklist where each point must be
satisfied for the port to work.
- The FreeRTOS port only works correctly in the supervisor mode. There-
fore the Coldfire CPU must run in the supervisor mode.
- portVECTOR_TABLE does not point to the currently active vector table.
Please also note that the vector table must be in RAM such that the
FreeRTOS port can install a traphandler for the portYIELD() call.
$Id: README.txt,v 1.1 2006/08/30 23:18:06 wolti Exp $
MCF5235 + lwIP port - Copyright (c) 2006 Christian Walter.
