This is the stopwatch board I built for measuring the video latency of our video processing board.
The main MCU is ATmega16-8PU which is running at 4MHz clock, provided by the 4MHz oscillator. All of the segments of the 7-segment LED display are driven by individual I/O pin. That means it is not driven by the conventional scanning method. In this way, I can achieve higher response time which is critical when doing the video latency measurements.
Also, the display pattern is not conventional 0~9 digits, but special design simple patterns are used instead. This improves the readability when it is switching from current to next pattern.
A Start-Stop-Clear button is shown on the board (the blue one). Three power sources are provided. But the USB power is not usable because the board seems to drain too much current.
The 10-pin JTAG connector is there to help debugging and burning firmware into the internal flash of the MCU.
