From the Windows Help Files:
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To input characters that are not on your keyboard:
1. Press and hold the ALT key, and then press the keys on the numeric keypad that represent the decimal code value of the character you want to input.
2. After you finish typing, release the ALT key.
Windows generates the character you specified.
Notes:
- If the first digit you type is 0, the value is recognized as a code point, or character value, in the current input language. For example, when your current input language is US-English (Code page 1252: Windows Latin-1), pressing ALT and then typing 0163 on the numeric keypad produces £, the pound sign (U+00A3). When your current input language is Russia (code page 1251: Windows Cyrillic), the same key sequence produces the Cyrillic capital letter JE (U+0408).
- If the first digit you type is any number from 1 through 9, the value is recognized as a code point in the system's OEM code page. The result differs depending on the Windows system language specified in Regional and Language Options in Control Panel. For example, if your system language is English (US), the code page is 437 (MS-DOS Latin US), so pressing ALT and then typing 163 on the numeric keypad produces ú (U+00FA, Latin lowercase letter U with acute). If your system language is Greek (OEM code page 737 MS-DOS Greek), the same sequence produces the Greek lowercase letter MU (U+03BC).
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From the above, it would be apparent that the KeyCode table for a specific language would need to be developed before you can easily determine just what will display for a particular code.
If anyone wants to create such tables and forward them on to me, I will post them on my website for future reference. Or better yet, if you can find links to already existing tables, I will add those links to our website Documents page.
Just send the standard 256-code set. The Extended set is too vendor specific for me to want to fool with.