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Unread 11-02-2016, 13:32
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Jared Russell Jared Russell is offline
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Re: am-2899 Absolute Encoder

Quote:
Originally Posted by Ether View Post
When you do it that way, how do you ask the FPGA to give you the rising-falling and rising-rising from the same cycle?


You can't do it atomically to my knowledge. But rising-rising is pretty much constant from one sample to the next (the oscillator is thermally sensitive, so it changes slowly).

We initially implemented it as two semi-period counters (one for T(on) and one for T(off)), and as you'd imagine, there were synchronization issues near the rollover point...
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