Scrolling Text Display – Android App

The app operates the Commando controller board which in turn drives 7 LED strips that are 60 leds in length.  The 7 LED Strips form a 7-by-60 bit display that can scroll messages each with a different color.  The Commando board is a bluetooth device so it’s capable of being paired with an android phone.

The unit is based on a PIC micro-controller from Mirochip and the HC06 Bluetooth module from Wavesen. This module is configured as a WS2812 LED Strip controller and is available on Amazon.com. An Android app is also available for download from either NorseBridge or Amazon.

The WS2812 Controller Module has 7 ports featuring the JST B3B-ZR polarized header. Each port is identical and sends the same control command to its strip. Most LED strips use the JST-SM 3 jack as an interconnect. The Controller Module comes with one JST ZHR-3 to SM-3 plug adapter cable.

One to seven WS2812 LED Strips can be used with this module and the Mokungit brand is an acceptable choice.

The app creates 5 messages limited to 15 characters each. Each message is assigned its own color. At the top of the screen the message is on the right and can be edited by touching the screen. There is a button to the left of the message that sends the message to the display. The button changes color to match the color of the message. The color palette below provides 14 colors for use (if black is chosen the message is not shown). Below the color palette the brightness of the color can be selected using a sliding scale.

Below the message edit field is 3 buttons. The “NEXT MSG” button advances to the next message. The “STORE NVM” button permanently stores the displays current settings to a non-volatile memory so that if the power is interrupted the display will return to these stored settings. The “MODE RESET” button will force the Commando controller into the scrolling text mode (using other apps the controller can be placed in other display modes).

To control the display it’s first necessary to pair the display the Android App using the Bluetooth menu. Click the bluetooth logo () in the upper-right corner. Choose “Search for New Device” for the first time the app is connected.

The name of the display controller is “HC-06” and the pin (password) is “1234”.

After the app is paired with the display it’s a simple matter to step through the messages one at a time edit the contents, select the color, and send it to the display. When the display is setup as desired select the “SAVE NVM” button to make the settings permanent.

Below are 2 examples of the scrolling display in use at an oil man lodge in southern Texas. The first example is a 7-by-60 pixel display. Behind this display you can see the back side of the 2nd example.

The second example is a 7-by-30 pixel display in which the exact same LEDs are spaced further apart. Notice that the spreading of the LEDs effectively increased the size of the display while the letters remained just as easy to read.