See underneath, or find here:
xPC Target -> Host-Target Configuration -> Configuration Basics -> Target Boot Methods -> Removable Disk Boot Method
Create a Bootable Partition
(C:/Program Files/MATLAB/R2013b/help/xpc/gs/creating-a-bootable-partition.html
):Removable Disk Boot Method
After you have configured the target computer environment parameters, you can use a target boot floppy disk, removable drive, or USB flash drive to load and run the xPC Target™ kernel. This topic describes using xPC Target Explorer to create a removable boot disk.
If you are creating a removable boot disk from a USB flash drive, before performing this procedure, you must create a bootable partition on the drive. See Create a Bootable Partition.
To create a removable boot disk using MATLAB® language, see Command-Line Removable Disk Boot Method.
To create a removable boot disk:
In the MATLAB Command Window, type xpcexplr.
In the Targets pane, expand the target computer node.
On the toolbar , click the Target Properties icon .
Select Boot configuration and set Boot mode to Removable Disk.
If you are creating a removable boot disk from a USB drive, insert the USB drive in the host computer USB port. Wait for it to be recognized.
Click Create boot disk.
In the Removable Disk Selector list, select the drive.
If required, insert an empty removable disk in the host computer drive and click OK. A progress bar is displayed.
When the write operation has finished, remove the removable disk from the drive or USB port.
Insert the removable boot disk into your target computer drive or USB port. Restart the target computer.
Press Enter, then click the Save icon on the toolbar.
Repeat this procedure as required for each target computer.
The next task is Run Confidence Test on Configuration.
Create a Bootable Partition
Before you create a removable boot drive from a USB flash drive, you must create a bootable partition on the drive:
On the host computer, open a DOS command window.
In the DOS command window, type:
diskpart
At the diskpart prompt, type:
list disk
Note the disk numbers of the existing host computer disks.
Insert the flash drive. Wait for the host computer to recognize the drive. Note the drive device name.
At the diskpart prompt, type:
list disk
Note the new disk number N. This number is the disk number of the drive.
Type:
select disk N
Caution The clean command deletes all of the data from disk N. Select the correct disk, or you might delete all of the data from your host computer.
Type:
clean
create partition primary
select partition 1
active
format fs=fat32 quick
exit
In the host computer task bar, click Safely remove hardware and eject media and select the flash drive name.
Remove the drive from the host computer.