Twiddler2 Scan Codes

Under all Microsoft operating systems, all keyboards actually transmit Scan Code Set 2 values down the wire from the keyboard to the keyboard port. These values are translated to Scan Code Set 1 by the i8042 port chip. The rest of the operating system, and all applications that handle scan codes expect the values to be from Scan Code Set 1. Scan Code Set 3 is not used or required for operation of Microsoft operating systems. In the very early days of Windows NT®, an attempt was made to use the much more orthogonal Scan Code Set 3, but due to bugs in the implementation of this Scan Code Set on numerous OEM keyboards, the idea was abandoned

These keys may have additional "shift" and/or "unshift" scan codes preceding the Base Make code and following the Base Break code, depending upon the current state of Num Lock and the state of SHIFT key/s (when multiple keys are held down at the same time).

US key assignment	Base Make	Base Break
Insert	E0 70	E0 F0 70
Delete	E0 71	E0 F0 71
Left Arrow	E0 6B	E0 F0 6B
Home	E0 6C	E0 F0 6C
End	E0 69	E0 F0 69
Up Arrow	E0 75	E0 F0 75
Dn Arrow	E0 72	E0 F0 72
Page Up	E0 7D	E0 F0 7D
Page Down	E0 7A	E0 F0 7A
Right Arrow	E0 74	E0 F0 74

Num Lock ON	Precede Base Make code with	follow Base Break code with
Final Key only	E0 12	E0 F0 12
LSHIFT down + Final Key
RSHIFT down + Final Key
Both LSHIFT and RSHIFT down + Final Key

Num Lock OFF	Precede Base Make code with	follow Base Break code with
Final Key only
LSHIFT down + Final Key	E0 F0 12	E0 12
RSHIFT down + Final Key	E0 F0 59	E0 59
Both LSHIFT and RSHIFT down + Final Key	E0 F0 12 E0 F0 59	E0 59 E0 12

(Print Screen on US keyboards)

(Pause on US keyboards)