PS/2 Keyboard Driver Scan Code Support (Windows Embedded CE 6.0)
1/6/2010
Some PS/2 keyboards only support the AT scan code set and do not function with platforms whose keyboard drivers expect XT scan codes. All PS/2 keyboard drivers use AT scan codes instead of XT scan codes.
Although Microsoft provides only AT scan code to virtual-key libraries, the provided keyboard drivers support only XT scan codes. To convert existing keyboard drivers that support XT scan codes to drivers that support AT scan codes, modify the routine that gets the scan codes from the hardware, which is typically PFN_KEYBD_EVENT. Modification is necessary because of key-up notification differences and the need to notify the PS/2 controller or the keyboard to use AT scan codes. These changes are hardware platform dependent, but you can use any of the provided PS/2 keyboard drivers as a reference.
See Also
Concepts
Keyboard Driver Development Concepts
Layout Manager
Translating Scan Codes to Virtual-Key Codes