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A comment on Keyboard latency. Parent comment

Re:Keyboard latency by duskwuff on Monday October 16, 2017 @06:52PM (#15487301)
This is absolutely untrue for any PS/2 keyboard, as well as for most pre-PS/2 PC keyboards (incuding AT and XT keyboards). All keyboards have always had a microcontroller in them which is responsible for scanning the key matrix and sending output over the serial link. (In PS/2, it's also responsible for reading input to change the state of keyboard LEDs.) There is nothing analog about them whatsoever.

Here is a set of pictures of an IBM Model M, for instance. The microcontroller is clearly visible in the ceramic DIP40 package.

http://www.clickeykeyboards.com/model-m-gallery/1985-ibm-mod...

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Re:Keyboard latency by kevin_thibedeau on Monday October 16, 2017 @07:45PM (#15487573)
PS/2 and AT are also bidirectional protocols for controlling the LEDs, key repeat, and various other commands that at a minimum requires some sort of digital state machine to manage the interface.
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