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.
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.
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)