"8042" PS/2 Controller: Difference between revisions
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A little more "translation" info
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=== Translation ===
The original keyboards (using the old XT interface) used "scan code set 1". When the original interface was superseded, IBM wanted to use a newer scan
This translation is enabled by default; and can't be reversed in software. For example, if you receive the byte 0xB5 from the controller, then you can't know if the original data (sent to the controller by the device) was the byte 0xB5; or if it was the two bytes 0xF0, 0x33; or if it was the two bytes 0xF0, 0xB3.
For software to actually use "scan code set 2" (or "scan code set 3"), or to allow different types of PS/2 devices to be used in the first PS/2 port, you need to disable this translation to avoid having the data from the device mangled.
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