Objective Development Forums

Hi,

I'm clueless. After pluging in the device, nothing happens. There is some talk one the D+ D- lines - few longer dips (a reset?) and the usual differential signal, but still the same error "device malfunctioned". I'm using the Atmega16 chip. Fuse bits are programmed correctly. Idle state is 2.88 V D- and 55mV D+. Any ideas ?

I've made the powerswitch with same circuit diagram except those relays and transistors. I didn't use LE33 but two diodes configured serially to drop the supply from 5v to 3.6 volt.
The crystal oscillator is ok, supply line is clean. But nothing works and windows still barking usb malfunctioned.
Any suggestion?

If Windows complains about a malfunctioning device, there's most likely a very fundamental problem. Your postings suggest that you have checked the supply voltage and that the device is actually running at the external crystal clock, not internal RC oscillator.

Since the circuit is very simple, there's not much left to check. Have you verified that the connector is wired correctly? And that the interrupt is also connected to D+? You mentioned that you use an ATMega16. Have you changed the definitions in usbconfig.h according to your circuit? And have you recompiled the source code instead of using the supplied hex file?