Attended: Mengyuan, Creighton, Scott

• Updates:
• To Do:

• Updates:
  • Completed the program that saves the clock cycles in an array and prints out the result at the end. Our results were okay half the time and garbage the other time.
    • In trying to debug the problem, we noticed that there was sometimes a problem with the array being lined up properly. If a microphone triggers twice in succession, it may create two entries instead of one, which will offset that array and will cause all the differences to be skewed. We noticed that this may cause mic2 to appear to have been triggered before mic1, which results in a negative difference. This may be due to a lack of hysteresis - which is the detection of a signal going from HIGH to LOW. Because we're just using voltage comparators to detect when it is triggered, a signal hovering around the threshold may cause it to trigger falsely. A Schmitt trigger is a device that can achieve hysteresis.
    • Along with that problem, we were a little worried with our results for when it does work. Recall that we had to get within 0.3us for this method to be effective. However, we were seeing results that vary on the order of microseconds, which is too large. One possibility is that the interrupts may actually be blocking (i.e. mic1's interrupt prevents mic2's interrupt from triggering on time), which may alter our results.
  • Worked on the presentation.
• To Do:
  • To check if our interrupts are actually blocking, we can do a simple test where we look at the differences in activation times for the mics.
    • For example, if mic1 was triggered at times 0s, 1s, 2s, exactly, then that's a good sign since it's a constant 1s. However, if instead we see that it was triggered at times 0s, 1s, 8s, then we know that mic2 might have been blocking mic1 from activating.