On-line test of NoC is essential for its reliability. This paper proposed an integral test solution for on-line test of NoC to reduce the test cost and improve the reliability of NOC. The test solution includes a new partitioning method, as well as a test method and a test schedule which are based on the proposed partitioning method. The new partitioning method partitions the NoC into a new type of basis unit under test (UUT) named as interdependent components based unit under test (iDC-UUT), which applies component test methods. The iDC-UUT have very low level of functional interdependency and simple physical connection, which results in small test overhead and high test coverage. The proposed test method consists of DFT architecture, test wrapper and test vectors, which can speed-up the test procedure and further improve the test coverage. The proposed test schedule reduces the blockage probability of data packets during testing by increasing the degree of test disorder, so as to further reduce the test cost. Experimental results show that the proposed test solution reduces power and area by 12.7% and 22.7% over an existing test solution. The average latency is reduced by 22.6% to 38.4% over the existing test solution.

A considerable amount of routers and links remains idle after each mapping application onto the Network-on-Chip based many-core systems. Online path-based test method is a kind of self-test for these idle components. In this paper, a path-based fabric for NoC is firstly proposed. A path serves as the basic component, covering one link and its associated control logic in the routers. One possibility is to apply fault detection on the idle paths, while the other paths continue to operate normally. Moreover, this paper details the hardware implementation, targeting the stuck-at and bridging faults. It suggests a good trade-off between fault coverage, hardware overhead and test time. Experimental results show that the approach achieves 93% of the stuck-at faults in control unit and cover 100% of the stuck-at and bridging faults on the global link within 256 clock cycles.