As well as providing a layer of abstraction between the hardware and the QNX Neutrino, BSPs are a delivery mechanism for the IPL, the startup code, device drivers, utilities, and build scripts that define startup behaviors.
Typically, a BSP includes:
QNX provides the source code for most of these components. You can use this source code as a model if you need to write your own device drivers, or make changes to the IPL or startup code. In some instances, however, because of copyright and other legal restrictions, QNX doesn't provide the source code, but only the compiled binaries.
For the exact contents of your BSP, see the “About this BSP” section of the BSP User's Guide for your board.
When you generate an IFS, the generation process first looks for components to use in the BSP, and then looks in the SDP on your host system for components it can't find in the BSP. This mechanism means that you can also use a BSP to include both additional and custom components. For instance, if your board variant needs a custom foo.so, place your custom foo.so in the BSP. When you generate a new IFS, your custom file is used, and the one in the SDP is ignored.