Installing the online documentation is part of the usual MathWorks install process:
Documentation from a CD -- Start the MathWorks installer, and when prompted, select the Product and Documentation check boxes. Later, during the install process, you will be asked to insert the Documentation CD.
Documentation from a Web download -- If you update xPC Target using a Web download, and you want to view the documentation with the MathWorks Help browser, you must install the documentation on your hard drive. Start the Web installer, and as before, select the Product and Documentation check boxes.
Note
During the usual installation of xPC Target from a CD or a Web download, the PDF files for the documentation are not copied to your hard drive. When you select to install the documentation, only the HTML files are copied.