User`s guide

4 Embedded Option
4-6
StandAlone mode. The module xpcboot.com is executed from DOS. It loads
and executes any xPC Target application. The first argument given to
xpcboot.com is the name of the image file (*.rtb) to be executed. This image
file contains the xPC Target kernel and options, such as whether you are
communicating using a serial cable or TCP/IP, and the ethernet address you
have assigned to the target PC.
Since the xPC Target loader is just an ordinary xPC Target application, the
loader can be executed from
xpcboot.com.
Before starting the kernel, you must first boot the target PC under DOS. The
module
xpcboot.com is then automatically executed under DOS by
autoexec.bat. To boot the target PC under DOS, you must first install DOS on
the target PC boot device. The xPC Target Embedded Option does not have
specific requirements as to the type of device you use to boot DOS. It is possible
to boot from a floppy disk drive, hard disk drive, flash disk, or other device
where you have installed DOS.
DOS is only needed to execute
xpcboot.com and read the image file from the
file system. After switching to the loaded kernel, and then executing the xPC
Target application, DOS is discarded and is unavailable, unless you reboot the
target PC without automatically invoking the xPC Target kernel. Once the xPC
Target application begins execution, the target application is executed entirely
in the protected mode using the 32-bit flat memory model.
Restrictions
The following restrictions apply to the booted DOS environment when you use
xpcboot.com to execute the target applications:
•The CPU must be executed in real mode
•While loaded in memory, the DOS partition must not overlap the address
range of a target application
You can satisfy these restrictions by avoiding the use of additional memory
managers like
emm386 or qemm. Also, you should avoid any utilities that attempt
to load in high memory space (for example,
himem.sys). If the target PC DOS
environment does not use a
config.sys file or memory manager entries in the
autoexec.bat file, there should not be any problems when running
xpcboot.com.