Objective Development Forums

So.... I have wanted to make this project for a while:
http://macetech.com/blog/?q=node/46
And April 1 is approaching. I made some boards with the ATTiny 85, resistors, capacitor, no zener, no crystal. I flashed the hex into the chip. Plug it into a USB port.

USB Device not recognized
Device Status: Windows has stopped this device because it has reported problems. (Code 43)

It shows as an Unknown Device. Do I need specific drivers (that can be installed quickly)? Are there certain fuse settings? I think that I read somewhere about setting the fuses for the PLL of the ATTiny85?

Any further assistance would be greatly appreciated.

Correct me if I'm wrong, but doesn't this put 5V signals over the USB data lines? I don't see anything to drop the +5V from USB that powers the '85 I wouldn't connect this to anything I cared about. I'm amazed that the author of this project would remove the zener diodes just to save a few components (as stated on the page), while making it violate the USB spec and possibly damage the USB port.

Good call blargg!

Restarted a new project (codeandlife.com with ATTiny2313). Able to install the hardware driver and communicate with the 2313 when it was powered at 3.3V. Same set-up gives "USB Device not recognized" when powered at 5V.

Again...Thanks!

Hi,

Another solution would be to cut the connection to USB pin 1 (Vcc) and insert either a red SMD LED or two normal SMD diodes in series to drop the voltage from 5V down to about 3.5V - that's close enough to the 3.3V from the specs. I never had problems with the two-diodes-solution.

Ciao, Martin