The 'ABT8996 10-bit addressable scan ports (ASP) are members of the Texas Instruments (TITM) SCOPETMtestability integrated-circuit family. This family of devices supports IEEE Standard 1149.1-1990 boundary scan to facilitate testing of complex circuit assemblies. Unlike most SCOPETMdevices, the ASP is not a boundary-scannable device, rather, it applies TI's addressable-shadow-port technology to the IEEE Standard 1149.1-1990 (JTAG) test access port (TAP) to extend scan access beyond the board level.

Conceptually, the ASP is a simple switch that can be used to directly connect a set of multidrop primary TAP signals to a set of secondary TAP signals - for example, to interface backplane TAP signals to a board-level TAP. The ASP provides all signal buffering that might be required at these two interfaces. When primary and secondary TAPs are connected, only a moderate propagation delay is introduced - no storage/retiming elements are inserted. This minimizes the need for reformatting board-level test vectors for in-system use.

Most operations of the ASP are synchronous to the primary test clock (PTCK) input. This PTCK signal always is buffered directly onto the secondary test clock (STCK) output.Read more