Built-in self-test is a functional requirement that a complex electron
ic system must satisfy in order to provide efficient production testin
g and system maintenance. Effective solutions with minimum possible ha
rdware overhead are needed. With the advent of application-specific in
tegrated circuits, integration of functions conventionally performed b
y external instrumentation in a single test IC on a board has become a
reality. The paper gives an example of how advantage of user programm
able logic was taken in the design of built-in self-test for telecommu
nications equipment.