I'm left to guess what you need here but if an ON SCREEN KEYBOARD is required I believe Windows 7 has one and no need for a download.
More at http://windows.microsoft.com/en-us/windows7/Type-without-using-the-keyboard-On-Screen-Keyboard?SignedIn=1
recently got a bare bone kit, which had a combined input for mouse or keyboard. got around it with usb adapter, but is there any digital keyboard downloadable for mouse only?

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