MicroZed Chronicles リスト http://adiuvoengineering.com/?page_id=285
@ Adam Taylor blog
https://forums.xilinx.com/t5/Xcell-Daily-Blog/Introduction-to-the-Zynq-Triple-Timer-Counter-Part-One-Adam/ba-p/407537
Each TTC has two basic modes of operation: interval or overflow mode, plus the event timer.
Interval mode : The counter counts to a value contained within the interval register, counting either up or down, and generates an interval interrupt whenever the count reaches zero (when enabled).
Overflow mode : The counter increments or decrements from 0 to full scale. When the counter wraps around, the TTC generates an overflow interrupt.
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The event timer can be used only with an external source and is a resource you can use to measure an event’s duration or to decode a PWM signal.