AN2757 Freescale Semiconductor / Motorola, AN2757 Datasheet - Page 11

• Manufacturer Part Number: AN2757
• Description: MPC5200 Quick Start
• Manufacturer: Freescale Semiconductor / Motorola

vectors, placement of code and variables into RAM and defines a software stack of a reasonable size (256kB). The Linker
Command File syntax used in CodeWarrior is described in the “Targeting Embedded PPC” User Manual located in the
CodeWarrior “Help\PDF” folder.
Unlike the linkers from other vendors, CodeWarrior’s Linker Command File syntax does not support the “AT” or “LOAD” directives
which are typically used when building a compact “image” suitable for writing into non-volatile memory. Instead of this feature,
there is a “Generate ROM Image” check box in the CodeWarrior linker settings. With this option enabled, when the linking is
finished, the linker walks through all initialized memory sections and puts them one after one starting at the specified ROM-image
address. Simultaneously, it generates a special array of data structures in which the original and ROM-image addresses are
specified for each such section.
In the MPC5200_Quick_Start, there are two targets that make use of the “Generate ROM Image” feature of the linker.
5.2.3
Debugger initialization and configuration files are used by the CodeWarrior whenever it is about to connect to the board over a
BDM interface. There are two kinds of Debugger files, both selected for each project target in the project settings window
(Figure
There are two Target Initialization files available in the MPC5200_Quick_Start. The first one is used by all projects and project
targets:
Freescale Semiconductor
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The “ROM Image” target uses this feature to build an self-extracting image, which can be run by the firmware code. In
a startup code of the image, the image uses the information from the CodeWarrior Linker-generated descriptor array
and copies all memory sections from the ROM Image to the destination addresses in RAM.
The “Standalone BL” target uses this feature similarly like the “ROM Image”, except that the SDRAM controller and
SDRAM memory are initialized before the ROM Image is extracted. See
details.
Target Initialization File: uses very simple language to initialize the PowerPC core registers and MPC5200 memory-
mapped control registers. Typically, its job is to configure Flash access space, SDRAM controller and SDRAM memory
before the Debugger downloads the application for debugging or before a Flash Programmer begins its operation.
Memory Configuration File: describes the memory area of the target system. Using a simple language, the memory
regions can be declared as Read/Write, Read Only or No-Access. A CodeWarrior Debugger uses the information from
this file when it is about to display the content of a memory or memory-mapped registers. This file is applied also when
processing a Target Initialization File, so the memory locations accessed by script in the Target Initialization File must
also be defined as valid (Read/Write) in the Memory Configuration File being used.
init_ram.cfg - initializes Flash memory space to be in range 0xFF000000...0xFFFFFFFF; initializes SDRAM controller
for 64MB RAM memory starting at address 0x00000000 and enables the PowerPC Core time-base counter (TB special
purpose register).
Debugger Initialization Files
AN2757 MPC5200 Quick Start and Graphical Configuration Tool
Figure 11. Project Linker Settings
Section 4.3.1, Lite5200 Boot Process
Application Framework
for more
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