Objective Development Forums

Hello,

I test ATtiny45 (with internal RC timing) with AVR-USB. It work fine until PC is powered down (also with device), and powered again on with connected ATtiny. ATtiny contain simple PWM application (LED blinking), and when WXP starting, device sometimes stop response (2 from 3 times), and fail to enumerate with VID/PID 0 (repeatedly). This never happen when device is connected after I'm logged in XP. Could be there problem with USB bus initialization in AVR-USB, or between my keyboard and chair?

Thank,
Slavo T.

got the same problem.
i hope someone of the developers knows anything about that.
i'm just wondering how to do a firware-based workaround and forced re-connect.
how could the avr detect, that it isn't properly connected?

bye,
tilex.

This may be an issue with RC oscillator calibration. Which method of calibration do you use?

I have discovered that, at least on the PCs I have been testing, setting USB_CFG_IMPLEMENT_HALT = 1 results in perfect behavior on resume. It really doesn't add that many bytes to the code, in exchange for the USB device working perfectly after the PC returns from sleep mode. It even works fine if the USB device is plugged into the computer while sleeping or off.

Interesting. Does this affect devices with interrupt endpoints only, or also custom class devices?

And can you track it down to a particular request, e.g. CLEAR_FEATURE or SET_FEATURE for an endpoint?

I've been seeing the same, I'll try the halt suggestion below and if I still have issues I could plug it into the Catc analyser at work and see what happens at reboot