Abstract: In one embodiment of the invention, a programmable logic device includes a plurality of programmable resources; non-volatile configuration memory adapted to store configuration data for configuring the plurality of programmable resources; a register adapted to load configuration data into the non-volatile configuration memory; and test circuitry coupled to the register. The test circuitry is adapted to configure a programmable resource with test data stored in the register rather than with configuration data stored in the non-volatile configuration memory. In another embodiment of the invention, the programmable logic device includes a buffer coupled between the configuration memory and a programmable resource, and the test circuitry includes a logic circuit coupled between the register, the configuration memory, and the buffer. The logic circuit is responsive to a test mode signal to route test data from the register to the buffer.

Abstract: A programmable logic device may comprise a plurality of programmable resources and non-volatile configuration memory to store configuration data by which to configure the programmable resources. Test override circuitry may determine a test mode and selectively override the configuration data stored in the non-volatile configuration memory during the test mode for configuring the programmable resources based at least in part on test configuration data other than the configuration data stored in the non-volatile memory. A buffer may be operable to drive a configuration select node for at least one of the programmable resources for designating a configuration therefore based on the configuration data of the non-volatile memory. The test override circuitry may comprise a pull-down circuit operable, when enabled dependent on the test configuration data, to drive the buffer with a high/low level capable of overriding a state of the non-volatile configuration memory.