On Wed 2018-03-21 14:57:33, Tony Lindgren wrote: > * Pavel Machek <pavel@xxxxxx> [180321 20:32]: > > Hi! > > > > > > Maybe get somebody to help you locally with the debug cable > > > > soldering? :) > > > > > > I suppose people from your hackerspace can help you. It's really > > > easy to do. Soldering can be avoided btw. You can just use a pair > > > of scissors to cut a USB -> Micro USB cable and use a knife to remove > > > isolation. Then screw each of the 4 wires into a terminal strip. > > > There are USB-TTL adapters available, that have an attached cable. > > > If you also cut the connector from such a cable and connect it to > > > the other side of the terminal strip you are done. No soldering > > > involved ;) > > > > Hm. How big no-no is connecting USB-TTL adapter to D+/D- pins? Because > > that's what I could do "easily" and seems to work ;-). > > Well if the VBUS line is not connected the PMIC is muxed > to USB carkit mode so the lines go to the UART on the SoC > through some level shifter. If it works it should not cause > any issues, the symptoms I saw earlier was corrupted UART > console and noticed that what worked best for me was 3.3V > ftdi based devices out of the collection of random pl2303 > and ftdi cables I had around. So.. I do have some fun on the UART (^@ inserted). > I guess somebody could try to measure the uart lines with > a scope with nothing connected and sending out data from > droid 4. Or look at the carkit spec for the UART voltage > levels. Voltmeter says Droid4 transmits at 3.3V. Anyway, it now works for me well enough that I can attempt to debug the .config file :-). Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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