If your "G3" has a built-in USB port, I assume that it's a Blue & White G3 mini-tower which you've described as a "desktop" model in your profile. If you're running OS 9.2.1, the built-in USB support drivers are already installed. If you have a beige G3 desktop model, then you must have already installed a USB PCI card. If the USB card was installed after the OS was installed, then the USB support drivers would not have been installed. If you're running the same OS version on your iMac and it has a CD burner, burn a Mac-formatted disk with the USB Support drivers listed below. The G3 should be able to read the burned CD and you can copy the drivers to the Extensions folder. Before that, I'd recommend running the OS 9.2.2 Update. When running OS 9.2.2, USB device recognition and functionality require these drivers in the Extensions folder:
(1) USB Support (OS 9.2.1 Update)
(2) USB Mass Storage Support (OS 9.2.1 Update)
(3) USB Device Extension (OS 9.2.2 Update)
(4) USB Software Locator (OS 9.2.2 Update)
(5) HID Library (OS 9.2.2 Update)
(6) EnetShimLib (OS 9.2.2 Update)
(7) SerialShimLib (OS 9.2.2 Update)
The first (2) weren't updated by the OS 9.2.2 Update, while the other (5) were updated. It doesn't matter how you get them installed in the Extensions folder, as long as they're present and enabled through the Extensions Manager Control Panel. The fastest method doesn't involve reinstalling the System software or running a custom installation of any part of it. Download "TomeViewer" and use it (like "WinZip" on a PC) to extract the specific drivers that I've listed from the System Software "Installation Tome" found in the OS 9.2.1 and 9.2.2 Updates. You can extract them directly to the Extensions folder, and after a restart, your USB PCI card and connected peripherals should function normally. Obviously, USB keyboards with specialized function keys will need the manufacturer's specific driver installed, but an OS 9.x-compatible driver may not be found on the included installation disk. You may have to settle for basic keyboard function, which you will have with the Apple USB support drivers. Additionally, a PC USB keyboard can be used with your Mac. Just remember that the Windows logo key is the equivalent of the Apple Command key and the Alt key is the same as the Apple Option/Alt key. In relation to the space bar, these two keys are reversed on the PC keyboard layout, when compared to a Mac keyboard.
