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A comment on Desktop compositing latency is real. Parent comment

Re:Desktop compositing latency is real by mark-r on Tuesday November 21, 2017 @12:34PM (#15749681)
I don't understand why someone hasn't come out with a dedicated keyboard chip yet. If it's cheap enough you don't need to run all the keys to a single chip, you could have multiple chips that all talk over a serial bus to one that it designated the master.
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Re:Desktop compositing latency is real by thesmok on Wednesday November 22, 2017 @05:01AM (#15755643)
Another layer of serial interfaces would make it even slower.
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Re:Desktop compositing latency is real by brokenmachine on Thursday November 23, 2017 @12:35AM (#15763032)
A serial interface can run a lot faster than anyone can type, eg i2c high speed is max 3.2Mbit/s.

SPI can be way faster than that I believe.

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Re:Desktop compositing latency is real by thesmok on Thursday November 23, 2017 @05:02AM (#15764070)
true, but adding another link (microcontroller) in the chain is going to add delay anyway. I think the original suggestion was pointless: instead of adding more microcontrollers you can just replace the main uC with the one that has enough pins. The reason this is not done is uCs with >100 pins are usually more powerful and expensive, so you can't just pay for more pins -- you also have to pay for more processing power and features you don't need.
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Re:Desktop compositing latency is real by mark-r on Wednesday November 22, 2017 @08:39AM (#15756656)
Depends on the speed/latency of the interface. Although you could probably say the same about the scanning matrix too.
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