ARM Compiler toolchain Using the Linker - ARM Information Center

8.1 About scatter-loading
8.1.1 See also
Using scatter files
The scatter-loading mechanism enables you to specify the memory map of an image to the linker
using a description in a text file. Scatter-loading gives you complete control over the grouping
and placement of image components. You can use scatter-loading to create simple images, but
it is generally only used for images that have a complex memory map. That is, where multiple
memory regions are scattered in the memory map at load and execution time.
An image memory map is made up of regions and output sections. Every region in the memory
map can have a different load and execution address.
To construct the memory map of an image, the linker must have:
• grouping information that describes how input sections are grouped into output sections
and regions
• placement information that describes the addresses where regions are to be located in the
memory maps.
When the linker creates an image using a scatter file, it creates some region-related symbols.
The linker creates these special symbols only if your code references them.
Concepts
• The image structure on page 4-3
• Region-related symbols on page 7-5
• When to use scatter-loading on page 8-4
• Scatter file to ELF mapping on page 8-67.
Developing Software for ARM ® Processors:
• Scatter-loading file with link to bit-band objects on page 3-16.
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