On Fri, Oct 16, 2015 at 2:52 PM, Hans de Goede <[email protected]> wrote: > Hi, > > On 15-10-15 16:58, Benjamin Henrion wrote: >> >> Hi, >> >> I got Q88 tablet with a broken screen from the flea market for 4EUR. >> >> Soldered the pins on the back for the serial port, got the console >> working by powering the device from the USB port AND from the 5V DC >> with a Nokia plug: > > > Hi I've bought a couple of q8 tablets the same way :) > > So you say pins on the back, so I assume that this is an A13 device ? > > A number of things: > > 1) Try building the latest upstream u-botot (from git master) with > the q8_a13_tablet_defconfig, and write that to an sdcard using: > > sudo dd if=u-boot-sunxi-with-spl.bin of=/dev/sdc bs=1024 seek=8 > > Adjust /dev/sdc to point to your sdcard ! > > 2) You say nokia plug, are you using a nokia charger ? The A13 based > boards will draw up to 2A when charging, and most nokia chargers > cannot deal with this, this also likely explains why you also need > to hookup usb too. Make sure you've a decent 5v 2A power-supply > hooked up to the power-barrel > > 3) The output you're seeing on the serial console is from the > part of the firmware which manages charging, if the battery is > too empty / your charger not powerful enough it will never get > past that. What you can do is: > > a) insert microsd with u-boot from step 1. > b) press the power button for 12 seconds, this forces the board to go really > off. > c) press the power button for 4 seconds > > Now you should see u-boot from the sd booting, and assuming only > the digitizer is broken and not the lcd you will also see a tux > on the lcd :) > > > > If the lcd works, you can order a new digitizer here: > > http://www.aliexpress.com/item/7-inch-Black-Touch-Screen-Digitizer-Glass-Touch-Panel-Allwinner-A13-Q8-tablet-pc-replacements-free/32213685488.html > > This will cost you another 4 euro :) > > But before doing so, measure the black bezel of the > digitizer on the top (camera) and bottom sides. On most tablets > it is 9 (top) / 10 (bottom) mm but on some it is only 7 / 8 mm, > the replacement digitizers by default are 9/10 and loosing 2 mm > of the screen on the top / bottom is quite annoying since that is > where status icons / start menu / etc. typically are. > > If you've one of the 7 / 8 mm tablets, look at the part number > on the wire coming out of the digitizer and search for that > on ali express, likely you need this one: > > http://www.aliexpress.com/item/Free-shipping-to-send-7-inches-100-original-brand-new-tablet-touchscreen-CZY6075E-FPC/32291760888.html > > Note that the part-number is not only in the "subject" of the > advertisement but also in the "Model Number" entry in "item specifics" > this is important, otherwise you will still get the wrong digitizer. > > Also note that this one is twice as expensive as the more standard one. > > If the lcd is broken I would not bother with repairing the tablet, > if you want to replace the lcd you must also replace the battery > as their glue-ed together and forcibly removing the battery > will bend it, rendering it unusable (using bend lipo batteries > is a fire-hazard).
The glue might not be that strong. I successfully replaced the LCD in my A13 tablet. It's best to use a knife to cut through the glue, and not just pry it off. ChenYu > I hope this helps. > > Regards, > > Hans -- You received this message because you are subscribed to the Google Groups "linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
