Abstract: On account of the integration of modern test system is becoming more and more complex, the IEEE 1149.7 Standard puts forwards the test method of star-2 scan topology to meet the needs of using fewer pins to achieve boundary scan at present. On the basis of on the IEEE 1149.7 standard and in-depth study on the standard, the platform of Quartus II was used to design the star-2 scanning controller, which is validated by simulation. The results indicate that the test signal can be generated by the controller, which can meet the provisions of star-2 scanning signal of IEEE 1149.7 standard and the specified Mscan format and Oscan format.