Cannot switch device to developer mode

I’ve bought a new Poynt Smart Terminal (P3303 V2.0) which has initially been configured in “production mode”, I wish to switch to “developer mode” but I cannot bind the device.

I’m running Ubuntu (18.04).

$ adb devices
List of devices attached
P6SW175JS000835	unauthorized

I’ve also followed with no success this guide

09/30 15:16:48: Launching app
$ adb push /tmp/MyApplication/app/build/outputs/apk/debug/app-debug.apk 
/data/local/tmp/com.example.lrkwz.myapplication device unauthorized.
This adb server's $ADB_VENDOR_KEYS is not set
Try 'adb kill-server' if that seems wrong.
Otherwise check for a confirmation dialog on your device.
Error while Installing APK

Relevant environment info:

$ adb version  
Android Debug Bridge version 1.0.36
Revision 1:7.0.0+r33-2
$ groups
lrkwz adm cdrom sudo dip plugdev lpadmin sambashare docker
$ lsb_release -a
No LSB modules are available.
Distributor ID:	Ubuntu
Description:	Ubuntu 18.04.1 LTS
Release:	18.04
Codename:	bionic

Hi Luca,
The device needs to be unlocked before it can be used in developer mode


That is the problem.

  1. Put your device into fastboot mode by holding the power and developer button while the device is powered off. => OK

  2. Select Fastboot Protocol from the fastboot menu => OK

  3. Make sure you have the Android SDK tools installed on your computer => OK

  4. Run the command to initiate the developer mode process on Poynt Smart Terminal: fastboot flashing unlock => KO

    $ fastboot --version
    fastboot version 28.0.1-4986621
    Installed as /home/lrkwz/Android/Sdk/platform-tools/fastboot
    $ fastboot flashing unlock
    < waiting for any device >

The device is not listed in adb devices and the fastboot command is stuck.


Is is matter of adding a /etc/dev/rules.d/ definition such as this 51-android.rules

SUBSYSTEM=="usb", ATTR{idVendor}=="18d1", MODE="4e40", GROUP="plugdev" # Poynt

numeric id’s from lsusb