JTAG boundary-scan testing Definition

Testing that isolates a device's internal circuitry from its I/O circuitry. This testing is made possible by the Joint Test Action Group (JTAG) Boundary-Scan Test (BST) architecture that is available in all Intel devices supported by the Intel® Quartus® Prime software except EPC1 and EPC1441 devices. Serial data is shifted into boundary-scan cells in the device; observed data is shifted out and externally compared to expected results. Boundary-scan testing offers efficient PC board testing and provides an electronic substitute for the traditional "bed of nails" test fixture.

The full or partial JTAG BST architecture also supports in-system multidevice JTAG chain device configuration.