BSDL FILE
Many High Pin count devices have JTAG pins to allow board level connectivity testing between device pins. In those cases, the vendor needs to provide a BSDL file to describe the pins. Vendors like Broadcom, Freescale, Marvell, and Avago to name a few provide these BSDL files for their customers, which is great because many of the same vendors also lock their PDF files so that the customer can't cut and paste pin definitions from the datasheet into one of the manual formats previously discussed. If The Vendor provides one, it is usually available for download on their website, or the user can request a copy from their sales rep. This is an excellent means of obtaining very accurate component pinout information.
The picture below shows 2 sections of the BSDL file. The PortMap section provides all the pin names and pin types, and the pin_map_string section assigns a pin number to each pin in the port map. The PartBuilder tool reads the BSDL file, and gathers all the pinout info required for the device.
Sometimes the pin name in a BSDL file does not quite match the pin name shown on the datasheet. The PartBuilder tool provides a mechanism to rename pins read from a BSDL file to change the pin name to what the user wants to display. This allows the user to always use the BSDL file from a vendor without having to modify it.
The Renaming is handled by the RENAME_RULES variable which can either contain a list of renaming rules or point to a file that contains renaming rules. The rename rule is a simple WAS:IS rule where any instance of WAS in a pin name is replaced by IS.
Figure 5: BSDL FILE SHOWING PORT MAP and PIN MAP Sections