History of BSDL; Definition

JTAG Boundary-scan is a well established test technology. JTAG Boundary-scan has been in use since the early 1990s when the Joint Test Action Group (JTAG) devised a solution to testing the many new printed circuit boards that were being developed and manufactured where there was little or no physical access for test probes. Once boundary-scan was established, the next step was to develop a standard modeling language for silicon vendors to model their boundary-scan devices, for tool vendors to develop automation tools, and for end-users to create boundary-scan tests. Thus the Boundary-Scan Description Language (BSDL) was created.

BSDL is the standard modeling language for boundary-scan devices. Its syntax is a subset of VHDL and it complies with IEEE 1149.1-2001. It is used by boundary-scan test developers, device simulators, semiconductor testers, board level testers, and anyone using boundary-scan. The use of BSDL promotes consistency throughout the electronics industry. Additionally, it enables the specification of any boundary-scan functions on a device in a useful, understandable, and consistent manner.

BSDL came out of the development of the boundary-scan test philosophy. The initial IEEE 1149.1-1990 standard describing boundary-scan was approved and released in 1990, and as a result the use of boundary-scan techniques started to grow. The next revision of the standard occurred in 1993. In 1994 a further revision incorporated BSDL into the IEEE 1149.1-1994 standard.

Source: TI Wiki