Category: Boundary Scan

It’s been great to reconnect with our Boundary Scan customers across the United States and Europe over the last several months discussing the new and exciting projects they have in the works. It’s also exciting to learn how our Boundary Scan product, ScanWorks, will play an integral role in the test, debug, validation, and deployment of these products. During one of these recent visits to a company that I consider a real power user of ScanWorks, the engineering manager who was participating in the meeting asked, “What is the best way for our new engineers to learn Boundary Scan?”
In addition to the BC_1 Boundary Scan cell type, there are more Boundary Scan cell types that can be used to create a Boundary Scan Register and implement the IEEE 1149.1 operations within a Boundary Scan device. The type(s) of Boundary Scan cell(s) implemented within a device are listed in the BSDL. Basic Cell (BC)_0 through BC_7 are the standard Boundary Scan cell types commonly found in an IEEE 1149.1 compliant Boundary Scan device. You may ask the question, “Are there more Boundary Scan cells than BC_0 through BC_7?”
Boundary Scan Description Language (BSDL) provides a description of testability features within ICs that comply with the IEEE 1149.1 Standard (hereinafter used interchangeably with the term “JTAG”). Having a good understanding of the BSDL leads to a deeper knowledge of JTAG, that in turn grants insight into the technology behind IEEE 1687, also known as IJTAG.
The 2013 Revision of the IEEE 1149.1 Standard incorporates support for dynamic data registers that can change in length and organization, unlike those fixed ones specified by the 2001 Revision. This allows, for example, definition of “excludable segments” for the boundary scan register (BSR); perfect for dealing with BSR segments in different power domains, some powered up and some not. How does this work?