Advanced processes are driving rapid growth in testing with a need for new approaches to testing at higher speeds. High-speed scan testing for IEEE 1149.10 has provided one option. Serial scan testing requires a handshake between the high speed serial and JTAG ports, which has introduced challenges for traditional ATE test methods. Dual time domains for high-speed serial lanes and setup patterns are required to start both together or to execute one while the other one is in keepalive. In cooperation with the electronic design automation (EDA) vendor Siemens Mentor and the ATE Software vendor Test Insight, Teradyne has created a test solution for our tester platforms. This presentation will discuss the challenges of serial scan testing and review the TestInsight ATEGen software solution for IEEE 1149.10 pattern generation to convert Mentor STIL files to ASCII pattern files on the UltraFLEX and UltraFLEXplus testers.