Using Nexmosphere and Taurus NovaStar

Step-by-step guide to enable ADB on a NovaStar Taurus TB40 via ViPlex Express and connect a Nexmosphere sensor board for interactive OnSign signage triggers.

Overview

This guide walks you through connecting a Nexmosphere sensor board to a NovaStar Taurus TB40 running OnSign, enabling interactive sensor-triggered content.

Requirements

  • NovaStar Taurus TB40 with OnSign TV installed and running
  • Windows PC on the same network as the TB40
  • ViPlex Express installed on the Windows PC
  • Nexmosphere sensor board + USB-Serial cable
  • ADB installed on your Windows PC (Installing ADB on Windows)

If you haven't installed OnSign TV on your NovaStar Taurus device yet, follow this guide first: Installing OnSign on NovaStar Taurus (Android).

Phase 1 — Hardware & Network

Step 1 — Power on the TB40

Plug the device into power and wait for it to fully boot before proceeding.

Step 2 — Connect to the internet

Connect via Ethernet cable or Wi-Fi. Confirm network access by navigating to the Android home screen.

Phase 2 — ViPlex Express: Enable ADB

Step 3 — Open ViPlex Express and connect to the TB40

Double-click the ViPlex Express icon to launch the application. Connect your PC to the TB40 using one of the two methods below:

Option A — USB Cable Option B — Wi-Fi
Connect your PC to the USB-B port on the front of the TB40 using a USB-B cable. Connect to the Wi-Fi network named AP+<SerialNumber>. Password: 12345678 (or check the sticker on the side of the unit).

Once connected, the Taurus device will appear in the ViPlex device list automatically.

Step 4 — Unlock User Software

With ViPlex Express open, type novasoft anywhere on the screen (no text field required). This reveals a hidden option called "User Software".

Step 5 — Select User Software and connect to the device

Click User Software in the menu. Select your Taurus device in the left-hand column and click Connect.

Enter the credentials when prompted:

  • Username: admin
  • Password: 123456

The device will show a green connection icon once connected successfully.

Step 6 — Configure User Software settings

With the device selected, apply these two settings:

  • ADB communication → Enabled
  • PlayService (NovaStar internal player) → Disabled

ADB is now enabled on the device and ready for use from your Windows PC.

Phase 3 — ADB Shell: Sensor Setup

Make sure ADB is installed on your Windows PC before proceeding. See Installing ADB on Windows for instructions.

Step 7 — Open a command prompt in the ADB folder

Navigate to the folder where you extracted the ADB platform tools. Hold Shift and right-click inside the folder, then select "Open PowerShell window here" (or "Open Command Prompt window here").

Step 8 — Check that the device is visible

Run the following command to confirm the TB40 is recognized by ADB:

.\adb.exe devices

You should see your device listed as attached. If it does not appear, double-check that ADB communication is enabled in ViPlex Express (Step 6) and that the USB cable or network connection is active.

Step 9 — Open an ADB shell on the device

.\adb.exe shell

You are now inside the device's shell. Confirm you are running as root:

# Check current user
whoami

# If the output is NOT "root", switch with:
su

Step 10 — Plug in the Nexmosphere sensor board

Connect the sensor board to the USB 3.0 port on the back of the TB40. Then verify it was detected:

dmesg | grep -i usb

# Expected output (example):
# [ 1069.112982] usb 5-1: New USB device found, idVendor=067b, idProduct=23d3 ...
# [ 1069.113018] usb 5-1: Product: USB-Serial Controller
# [ 1069.113025] usb 5-1: Manufacturer: Prolific Technology Inc.

# Note down your idVendor and idProduct values

Step 11 — Register the USB device driver

Use the idVendor and idProduct from the previous step to bind the pl2303 serial driver:

echo "<idVendor> <idProduct>" > /sys/bus/usb-serial/drivers/pl2303/new_id

Step 12 — Configure the serial port baud rate

Set the communication parameters for the serial interface:

stty -F /dev/ttyUSB0 115200 raw cs8 -cstopb -parenb

# Parameters:
#   115200  → baud rate
#   raw     → raw mode (no processing)
#   cs8     → 8 data bits
#   -cstopb → 1 stop bit
#   -parenb → no parity

Step 13 — Confirm the USB serial port

Verify the device node is available:

ls /dev/ttyUSB*

# Expected output:
# /dev/ttyUSB0

✅ The sensor is now ready. Note that this configuration is lost on reboot — follow Phase 4 to persist it.

Phase 4 — Persistence: Auto-configure on Reboot

Step 14 — Make sure you are root and remount /vendor as writable

Before editing system files, confirm you are running as root. The su command from Phase 3 only applies to that shell session — if you opened a new shell or your session changed, switch to root again:

whoami

# If the output is NOT "root":
su

mount -o rw,remount /vendor

Step 15 — Create the boot init script

Write the initialization script to a persistent location. Replace <idVendor> and <idProduct> with the values found in Step 10. The sleep 15 gives the system time to fully load USB drivers before running.

cat > /data/local/tmp/usb_serial_init.sh << 'EOF'
#!/system/bin/sh
sleep 15
echo "<idVendor> <idProduct>" > /sys/bus/usb-serial/drivers/pl2303/new_id
log -t usb_serial "PL2303 ID added"
EOF

chmod 755 /data/local/tmp/usb_serial_init.sh

Step 16 — Register the service in the init RC file

Append a service definition to the device-specific RC file. This tells Android's init system to run the script automatically once boot is complete.

cat >> /vendor/etc/init/hw/init.rk30board.rc << 'EOF'
service usb_serial_init /system/bin/sh /data/local/tmp/usb_serial_init.sh
    class late_start
    user root
    group root
    oneshot
    disabled
    seclabel u:r:shell:s0

on property:sys.boot_completed=1
    start usb_serial_init
EOF

ℹ️ The service is triggered by sys.boot_completed=1 — it fires once after every reboot.

Step 17 — Remount /vendor as read-only

Restore the partition to its secure read-only state after editing.

mount -o ro,remount /vendor

✅ The configuration will now persist across reboots.

The Nexmosphere sensor is now configured and ready to communicate with your NovaStar Taurus device. The final step is to configure the serial port in the OnSign Platform so the player can receive and process sensor events.