A broken GRiD 1550SX laptop like the ones used in the movie "Aliens" was converted to a Raspberry Pi and Teensy laptop. Simon did an incredibly clean conversion that includes using the original keyboard plus the IsoPoint roller bar mouse. I assisted by writing the Teensy LC code for the keyboard and IsoPoint. The IsoPoint precedes PS/2 touchpads that eventually became the standard for laptops. The IsoPoint uses rotary incremental encoders which the Teensy converts to USB. The Teensy code can be found on Github.
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