Business card draws [ch00f]‘s logo


[ch00f] is at it again, expanding the horizons of the art of PCB business cards. This one draws his logo on any computer over a USB port.

The physical design of the card is heavily inspired by [Frank Zhao]‘s card; both use an ATtiny85 and the V-USB package to handle the USB protocol and communications. Instead of typing words into a text editor like [Frank]‘s, [ch00f]‘s card draws the ch00ftech logo in MS Paint or other image editor.

There was a problem with simply emulating the mouse to draw a logo on the screen, though; because different computers have different mouse settings for acceleration, the ch00ftech logo was nearly always distorted. [ch00f] fixed that by emulating an absolute input device, basically turning his business card into a single-function pen tablet.

The logo was traced by hand and put into a few arrays in the firmware. Surprisingly, the logo didn’t take up much space – only 4k of the tiny85’s flash is used. There’s a lot more space for a more complicated drawing, but for now the simple ch00ftech logo (video after the break) will do.


  1. Matt says:

    Cool, but a bit oldschool. I prefer NFC business cards

    • biozz says:

      i used to have them … there only useful i found when having a frined take your cell info … i now keep just one in my wallet just so people can scan my wallet
      i personally prefer ones with QR codes (simple but shockingly effective seeing how few people i have to give them to have/use NFC) and there cheap to make a bunch
      but i would love a few USB ones like this or similar for the few clients making it work my while!

  2. biozz says:

    i love this guys work!

  3. threepointone says:

    AHH another really cool design today! ^ I agree, love this work.

  4. Rafael Carrascosa says:

    I wonder if how he gives a written offer for the source code or the source itself along with the card… since it’s using V-USB and that’s GPL.

  5. Greenaum says:

    A relative of mine works for a company that makes business cards where a thicker piece, on the bottom edge, snaps off. It’s the same thickness as a USB plug. So you slide it in a USB port, and it’s a useful flash drive, I think a couple of GB.

    Unfortunately it looks like, after that, you’d just throw away the main card piece, so kinda pointless. Though the remaining flash drive can still have your website and phone number printed on it.

  6. Tom the Brat says:

    V-USB requires a faster clock than the Tiny85 has, doesn’t it?

    Perhaps you use the OSCCAL to crank it up?

    • Suki says:

      from the wiki:
      V-USB can currently handle clock rates of 12 MHz, 12.8 MHz, 15 MHz, 16 MHz, 16.5 MHz, 18 MHz and 20 MHz. These clock rates are precise! A crystal with 11.9 MHz won’t work! Only the 16.5 MHz and 12.8 MHz variants allow a deviation of up to 1%. They are therefore suitable for RC oscillators. 16.5 MHz is suitable for devices which can derive a 16 MHz clock from an RC oscillator (e.g. ATTiny25/45/85 and ATTiny26), 12.8 MHz can usually be reached by calibrating the 8 MHz RC oscillator. Calibration of the RC oscilator is described at examples.

      I’ve used v-usb on several Attiny45/85 using the built-in RC oscillator and it works like a charm :)

  7. Selena says:

    Love it Cuiffo!

  8. Ivan says:

    Nice and all, but how did he install Windows 7 on MacBook Pro?

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s


Get every new post delivered to your Inbox.

Join 92,182 other followers