I think I finally found out what the problem is:
After I bought
and plugged everything in, I had no problems what so ever.
BUT this voltage tester has two USB outputs.
The first one works like the USB port on the computer
The second one works like a simple charger.
The Fairphone 2 works perfectly normal on the first USB port, but has the described problems on the second USB port.
The EzReal Support also wrote, that on the second USB port D+ and D- are short-circuited due to the fact that the second USB port acts like a normal charger USB port.
Does that make any sense? I’m not a electrical engineer, so I have no idea if everything I wrote was correct.
TL;DR;
I think it is a Software Bug on the Fairphone 2.
Somehow the Fairphone 2 needs the data channel (D+ and D- => see http://www.beyondlogic.org/usbnutshell/usb2.shtml) to be available. If this is not the case, the touchscreen simply freezes.
Hello all
I have the same issue, though i think “unusable” would be a strong word in my case.
At times, while charging, the touchscreen stops responding. Then the only way of waking it up is to unplug the charger, and toggle the screen off then back on.
But it only happens at times.
Okay, that’s really interesting. AFAIK, there’s 3 ways USB chargers handle the data pins:
Leave them unconnected to anything (common on the cheapest chargers);
Short them to ground. According to spec, this should indicate a dedicated charger;
Use resistor voltage dividers to show data lines at a specific voltage, that according to spec indicates a certain allowable charge current.
A 4th option is to have some IC send a signal over the data lines, I think recent Apple chargers do that. If the touch screen problems only occur on one or some of these types of chargers, that might indicate what the problem is? Unfortunately, I don’t have the equipment to see what my charger’s data lines are doing.
I do have a USB “charger” cord (no data lines), and using that with the wall charger seemed to make the problem worse. However, the phone still didn’t have this problem when I used that cord with a laptop USB port.
I’ve since received my replacement fairphone, and although it has the same issue it’s much less severe (to the point where I can live with it ). I guess this makes it seem more like a software problem, but there is some variability between individual phones. I’m very curious to see what will happen after the next software update.
To be fair, considering my landlord’s approach to home renovation I wouldn’t be shocked (or perhaps I would be ) to discover that the wall socket’s ground isn’t connected.
Hmm strange. Where are you located? How new are your “power cables” (the one in the house)? Maybe it has something to do with how the power gets to the phone…
Same problem here: while recharging the phone gets “wild”! I can’t use it well since it doesn’t work well when I tap icons or words or unlock patterns (the worst frustrating thing, guys!). Adding this trouble to the microphone not working well at all (people can’t simply hear me!) I must say that buying FP2 was NOT a good idea
Same problem here.
On some chargers the touchscreen gets totally unresponsive during charging.
I’m not sure if this is a problem with the charger or with the phone. It might be a hardware-problem or a software-problem with the fairphone 2, that is triggered by some chargers.