Archive: Key Support, Keyboard Scan Codes, and Windows

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	Scan Codes for Keyboard Power Switches
	Key Support for Microsoft Windows Operating Systems and Applications
	USB HID to PS/2 Translation Table

Scan Codes for Keyboard Power Switches

The following defines the correct scan codes for keyboard power switches for OnNow hardware:

Power event 
    Set1:    Make = E0, 5E    Break = E0, DE
    Set2:    Make = E0, 37    Break = E0, F0, 37
Sleep event 
    Set1:    Make = E0, 5F    Break = E0, DF
    Set2:    Make = E0, 3F    Break = E0, F0, 3F
Wake event 
    Set1:    Make = E0, 63    Break = E0, E3
    Set2:    Make = E0, 5E    Break = E0, F0, 5E

The Set 2 break codes also need the 0xE0 prefix, otherwise the system will see the new key going down but see some different key coming up.

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Key Support for Microsoft Windows Operating Systems and Applications

 Keyboard Scan Code Specification
(Revision 1.3a; 2.4 MB file Microsoft Word format; file date: February 23, 1999; revised March 2000) Previously published as "WHQL Keyboard Specification."
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The Keyboard Scan Code Specification details the PS/2 Scan Codes and USB Usage Tables that are validated for compliance to the WHQL testing standard. This document details the alternative make and break PS/2 scan code and USB code response for the Microsoft Windows Logo Key Application Keys and Advanced Configuration and Power Interface (ACPI) power controls.

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USB HID to PS/2 Translation Table

The USB HID to PS/2 Scan Code Translation Table provides a mapping from the HID keyboard/multimedia usages to PS/2.

 Download "USB HID to PS/2 Scan Code Translation Table" in PDF format
(134 KB .pdf file; April 9, 2004; Note: To view this document, it is necessary to use Adobe Acrobat Reader Version 4.0 or later and one of the Asian font packs.)

 Download "USB HID to PS/2 Scan Code Translation Table" in Microsoft Excel format
(63 KB .xls file; April 9, 2004)

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