11 University of Electronic Science Technology of China(UESTC) Sent High-level Voltage Recieved ECHO Over Flow TGetTime[O] GetTime[1] GPT Capture on rising edge Capture on falling edge TestTimeSum=(GetTime[1]-GetTime[O]) Time Duration=F(TestTimeSum) Real-Time Systems Lab11 Real-Time Systems Lab University of Electronic Science & Technology of China (UESTC) Over Flow GPT ECHO GetTime[0] GetTime[1] Capture on rising edge Capture on falling edge High-level Voltage TestTimeSum=(GetTime[1]-GetTime[0]) Time Duration=F (TestTimeSum) Sent Recieved