[Nav] wanted to change his keyboard mapping for one particular keyboard, rather than on each operating system. He used an AT90USBKey as a replacement PCB by soldering to all of the contacts on the key matrix. This allows him to remap the keys by following onscreen prompts.
The board enumerates as an HID device, and has a special mode which is accesses by plugging the keyboard in while holding down any key. If a text editor window is active you’ll see prompts from the microcontroller to press a series of keys. This is a routine used to learn how the key matrix is organized, and it’s your opportunity to change how each key is mapped. Since the mapping is saved to EEPROM, you can use any computer to map the keys, then plug the device into a systems that don’t offer software remapping. It could also be useful as a gaming keyboard, assuming there aren’t latency issues
As with the AVR-based arcade controller, this project uses the LUFA package to handle the USB stack.
The Genearic HID tool is meant as an easy way to create your own human interface devices. The project has the added benefit of showing us how to hack the hardware on the AT90USBKey developement board. The AVR-based device, which we saw used to make an SNES cartridge reader, comes in at just over $30 but with a few caveats. First, the breakout pads for the pins are not 0.1″ pitch and require some creative soldering to get at them easily. But the walk through also covers converting the board to run at 5v when in USB host mode, and altering the populated components to reclaim pins on the AT90USB1287 chip. The fun isn’t limited to this board, there’s also a home brew alternative based around the same chip.
Reader, [Matthias_H], sent in a video about his USB adapter for SNES game carts. All you have to do is plug in the SNES game cartridge and USB cable, then a ROM file of the game shows up as an external storage device on your computer. After that, you can play the ROM with your choice of emulator. We emailed [Matthias] asking for more information, and he quickly replied with a very nice writeup about the hack that is pasted below.
Update: [Matthias] launched a site for the “snega2usb” with updates on the development of the board and a FAQ.
Continue reading “USB reader for SNES game carts”