BSP Developer's Guide

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Creating a New BSP
...
#endif
}
The #include of usrExtra.c links in the other configuration files from
src/config. You do not need these now, but you will need them later as you add
features. For example, when you are ready to start working on the kernel and
the target agent, you need to link in the appropriate configuration code as
follows:
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#if FALSE
#include "usrExtra.c"
#else
#include "usrWdb.c"
#endif
3.3.2 Building and Downloading VxWorks
The VxWorks image you load to the target depends on the download method you
use. The primary images are as follows:
vxWorks
This image starts execution from RAM. It must be loaded into RAM by some
external means such as the board’s native debug ROMs.
vxWorks_rom
This image starts execution from ROM, but its text and data segments are
linked to RAM addresses. Early on it copies itself into RAM and continues
execution from there.
vxWorks_resrom_nosym
This image executes from ROM. Only the data segment is copied into RAM.
If your download path puts the image in RAM (such as when using a vendor
debug ROM), use vxWorks. If your download path puts the image in ROM (such
as when using NetROM), use either vxWorks_rom or vxWorks_resrom_nosym.
The advantage of vxWorks_rom is that it can be more easily debugged because the
software breakpoints can be set only on RAM addresses. The advantage of
vxWorks_resrom_nosym is that it uses less target memory. The makefile for both
ROM images lets you specify an optional .hex suffix (for example,
vxWorks_rom.hex) to produce an S-record, rather than an object file.
There is a file called depend.cputool containing the file dependency rules used by
the makefile. The makefile automatically generates the dependency file if it does
not already exist. If you add new files to the BSP, delete the dependency file and let
the makefile regenerate it.
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