Specifying memory map information for the image

Controls the automatic assignment of __at sections to execution regions. __at sections are sections that must be placed at a specific address. See Using __at sections to place sections at a specific address for more information.

If enabled, the linker automatically selects an execution region for each __at section. If a suitable execution region does not exist, the linker creates a load region and an execution region to contain the __at section.

If disabled, the standard scatter-loading section selection rules apply. See Input section description for more information.

The default is ‑‑autoat.

Enables commands to be passed to the pre-processor specified on the first line of the scatter file. You can also use the synonym:‑‑pd=”string”.

More than one ‑‑predefine option can be used on the command-line. Use this option with ‑‑scatter. Example 2.1 shows how the scatter file looks before pre-processing.

Scatter file:
#! armcc -E
lr1 BASE
{
    er1 BASE
    {
        *(+RO)
    }
    er2 BASE2
    {
        *(+RW+ZI)
    }
}

Use armlink with the command-line options:

‑‑predefine="-DBASE=0x8000" ‑‑predefine="-DBASE2=0x1000000" --scatter file

This passes the command-line options: -DBASE=0x8000 -DBASE2=0x1000000 to the compiler to pre-process the scatter file.

Example 2.2 shows how the scatter file looks after pre-processing:

lr1 0x8000
{
    er1 0x8000
    {
        *(+RO)
    }
    er2 0x1000000
    {
        *(+RW+ZI)
    }
}

Sets both the load and execution addresses of the region containing the RO output section at address. address must be word-aligned. If this option is not specified, and no scatter-load file is specified, the default RO base address is 0x8000.

Makes the load and execution region containing the RO output section position-independent. If this option is not used, the region is marked as absolute. Usually each read-only input section must be read-only position-independent (ROPI). If this option is selected, the linker:

Splits the default RO load region into two RO output sections, one for RO-CODE and one for RO-DATA.

Sets the execution addresses of the region containing the RW output section at address. address must be word-aligned.

Makes the load and execution region containing the RW and ZI output section position-independent. If this option is not used the region is marked as absolute. This option requires a value for ‑‑rw‑base. If ‑‑rw‑base is not specified, ‑‑rw‑base 0 is assumed. Usually each writable input section must be read-write position-independent (RWPI).

If this option is selected, the linker:

Creates the image memory map using the scatter-loading description contained in file. The description provides grouping and placement details of the various regions and sections in the image. See Chapter 5 Using Scatter-loading Description Files.

The ‑‑scatter option cannot be used with any of the memory map options ‑‑partial,‑‑ro‑base, ‑‑rw‑base, ‑‑ropi, ‑‑rwpi, ‑‑rosplit, or ‑‑split, and with ‑‑reloc, and ‑‑startup.

Splits the default load region, that contains the RO and RW output sections, into the following load regions:

Both regions are root regions. See Specifying the image structure for more information.