http://geekhack.org/showthread.php?p=204389#post204389
-Terminogy
+Terminology
---------
NKRO
ghost
OS Support Status
-----------------
USB NKRO is possible *without* a custom driver.
-At least following OSes supports.
+At least following OS's supports.
Windows7 64bit
WindowsXP
Windows2000 SP4
Custom Driver for USB NKRO
--------------------------
NOT NEEDED
-at least when using fllowing report formats on Windows, Linux or MacOSX.
+at least when using following report formats on Windows, Linux or MacOSX.
USB NKRO methods
If the keyboard has 2 virtual keyboard with Standard report(6KRO), it gets 12KRO.
Using this method means the keyboard is a composite device.
-2. Exteded report
- It needs large report size for this method to achive NKRO.
+2. Extended report
+ It needs large report size for this method to achieve NKRO.
If a keyboard has 101keys, it needs 103byte report. It seems to be inefficient.
3. Bitmap report
Compatibility
boot protocol
minor/old system
- Some BIOS doesn't send SET_PROTCOL request, a keyboard can't switch to boot protocol mode.
- This may cuase a problem on a keyboard which uses other report than Standard.
+ Some BIOS doesn't send SET_PROTOCOL request, a keyboard can't switch to boot protocol mode.
+ This may cause a problem on a keyboard which uses other report than Standard.
Reactivity
USB polling time
OS/Driver processing time