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USB generic interface board

Concept Wrap a Cypress EZ-USB controller chip into a prototyping and test board. This board can be used to develop small hardware projects for the PC, including but not limited to custom keyboards, joysticks, lights, and even little robots.

Current Status

I finally cleaned up the connections, got up my nerve, finished fully backing up my software, and plugged my circuit board into my Windows 2000 system. The great news, nothing died horrible deaths! I unplugged it and re-plugged it and it had the same behavior; so far so good. I have no drivers for it yet, and the USB software subsystem says to the effect of "something unknown is plugged in but no suitable drivers are installed". Hopefully this is a good sign. Now the task is to figure out basic Cypress EZ-USB drivers.

I got a perfect circuit board etch, and soldered my first full test board! I got the chip on, but may have a pin alignment problem. <sad face> I have the usb connector, smd resistors and caps, and the crystal all properly attached, though! A little cleanup with an exacto knife first, then hopefully I can confidently plug it in and see how it does.

I hope that just a little more playing with hardware will leave me with a working prototype board and that I can start playing with the software side of things. And then following that will be the Version2 hardware design (bringing out all 40 rather than just 16 I/O ports)and daughter boards, and so fort!


  • Electrical Engeneering/ Comp. Sci. hobbyist platform
  • Custom Keyboard Interfaces (Handicap, customized layouts)
  • Data Gathering/ Sampling/ Input
  • Unique peripherals (Arcade joysticks, Atari Disk Drive access)
  • Computer control of electronics, motors, relays


  • Wraps a Cypress EZ-USB chip in a 'project board' type application
  • Downloadable & editable 'driver' firmware for experimentation
  • easily attachable to project 'daughterboard'

Tools and Process

  • I use Toner Transfer Paper to print the circuit board with my nice HP LaserJet 1200. The paper is the "Toner Transfer System" (TTS) from
  • Then, using my SuperFuser, I apply pressure and heat to fuse the transfer paper to a copper clad pcb board. (It works better than a clothes iron!) After the SuperFuser the board+paper goes into a tub of water and the paper separates from the toner, and then I have a circuit printed on copper! The super fuser is again a product.
  • After the water bath, the circuit board-to-be is given an acid (etchant) bath, removing all exposed copper, leaving the circut as printed. I etch with Sodium Persulfate, giving more business to since they taught me how! However, my etchant tank is made inexpensively from a plastic tub from Target and an aquarium heater, pump and thermometer from PetSmart.
  • All that is left is to drill the appropriate holes and solder down the wires, components, and connectors! My cool small drill press and bits were happily sold to me from, and the soldering iron was from my local Future Active electronics store.
  • Viola! A circuit board.

Thanks and Links

  • Andy's IPAC board was my original eye-opener and inspiration: "A single chip USB controller! I wonder if I could do that?". Andy's at, and IPACs and more can be found at
  • After some research, I decided to work with a Cypress EZ-USB controller because of its downloadable firmware. That way there is no need to mess with EEPROMS for software testing. Very Cool!
  • A web search turned up the cool work that Edward Schlunder has done, and his work and occasional help has made my learning curve much less painful!
  • And without I would not have figured how quite to accomplish any of this in my apartment.
Thanks and Kudos to you all!


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Last Updated Jan-17-2002