On Mon, 7 Aug 2017 17:53:35 +0200 tu...@posteo.de wrote: > On 08/07 11:21, Stefan Mark wrote: > > On Sun, 6 Aug 2017 18:50:07 +0200 > > tu...@posteo.de wrote: > > > > > 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. > > > > > That usually happens when the improvised USB is not good enough. > > Try a different port, maybe put a USB Hub between. Check if the > > resistors and diodes for the level shifting are the right ones > > (measure the resistors, especially if you are not using 5% types). > > If that does not work, try a different diode/resistor combination > > (For example, usbasp uses 5v6 zener and 68/2k2 resistor, littlewire > > 3v6 zener and 27/1k2 resistor. I have seen others too. I had at > > least one which never worked with my laptop). > > The board is THAT tiny (http://digistump.com/products/1) that even > a single proble will short circuit one half of the board... :) Yeah, i know them. You need a smaller probe ;) But i can understand that, i would not like to change parts on those. Then better try other Ports :)
pgpEaF_puh301.pgp
Description: OpenPGP digital signature
