Samsung Galaxy J3 2016 (samsung-j3xnlte)

The Samsung Galaxy J3 (2016) (also called Samsung Galaxy J3 6) is an Android smartphone which was developed by Samsung Electronics and was released on January 15, 2016.

Contributors

 * Ster Please contact me on Matrix if you are at any step of the process, either by mentioning my username  or simply message me directly, I'd love to hear any success, failures, difficulties. I'm not necessarily going to be able to help you, since I've still got lots to learn but it'd be nice to chat.

Initial comments
Note that there are different models of the Samsung Galaxy J3. To see which one you have, if you still have the original recovery image on your device, power it off and then hold down the home button, power button and volume up button. See at the top of the phone's screen for the model code. If it's J320FN(string of characters) you're probably good to go. If yours is J320F it will probably be very similar to port.

How to enter flash mode
This is not used for flashing postmarketOS, but is used for flashing recovery partition with TWRP. See for details on why I do not recommend flashing postmarketOS with Heimdall.

Hold down home button, power button and volume down button for a number of seconds. Then once a prompt appears on screen, press volume up. You are now in download mode (it will say so on the screen).

Installation
Firstly, download TWRP from the XDA developers page. The download is in the section labelled "Attachments".

Use heimdall to flash  to the recovery partition of your device:
 * Put it in download mode (see above)
 * Connect to computer
 * Run  to see if heimdall can see it.
 * Run, making sure you are in the directory with

Now see the installation guide for details. Flashing via heimdall did not work for me, so instead follow the Android Recovery Zip installation guide instructions:

Run

to install to android recovery zip.

Boot your phone into recovery mode: power off and hold down volume up, power and home buttons. You should see the "Team Win" logo. Select "Advanced" then "ADB Sideload". Connect your phone to your PC. Swipe to start the flash. Next run

on your PC and watch as the postmarketOS ascii appears. Select reboot, and your display and touchscreen should work out of the box.

Charging-related recommendation
Disconnect the cable when you turn the device off. The device freezes on the charging splash screen if it's not disconnected.

Mainlining
SoC uses a custom hardware timer, which has to be ported before mainline can be booted.