Hi, sorry, this will become a little longish...
Background: To program an ATMEL ATtiny85 via USB without a dedicated USB chip there is a bootloader called "micornucleys", which bitbangs the USB protocoll. This mechanism is used in Digistupms Digispark ATTtiny developmnent board (http://digistump.com/products/1). So far so ....nice? When I plug in such a little board into my PC, demesg reports: [ 1429.834140] usb 7-4: new low-speed USB device number 15 using ohci-pci [ 1429.965142] usb 7-4: device descriptor read/64, error -62 [ 1430.203151] usb 7-4: device descriptor read/64, error -62 [ 1430.438161] usb 7-4: new low-speed USB device number 16 using ohci-pci [ 1430.569151] usb 7-4: device descriptor read/64, error -62 [ 1430.803174] usb 7-4: device descriptor read/64, error -62 [ 1431.038184] usb 7-4: new low-speed USB device number 17 using ohci-pci [ 1431.456157] usb 7-4: device not accepting address 17, error -62 [ 1431.582204] usb 7-4: new low-speed USB device number 18 using ohci-pci [ 1432.000209] usb 7-4: device not accepting address 18, error -62 [ 1432.000244] usb usb7-port4: unable to enumerate USB device or similiar. lsusb does not show anything related at all. As recommended on related pages on the internet, I installed dedicated udev rules to show the needed ttyACM device. But since the kernel itsself fails to accept the device, the best udev rules will not work. My first thought was: The micronucleus bootloaed is missing or is defective... But plugging in the board into my Android tablet (the tablet runs Lollipop and is nothing special at all beside being rooted) via an OTG cable and using lsusb after that, it shows Bus 001 Device 003 ID 16d0:0753 MCS Digistump DigiSpark dmesg reports for this device to use the modyle xhci_hcd. I loaded that module by hand on my Gentoo PC and reinserted the Digispark: Nothing...same errors as before. What can I do to make this Digispark being correctly recognized? Thank you VERY much for any help in advance! Cheers Meino