Vermes
Advanced Member level 4
It is another construction of Arduino used for blinking LEDs. What makes this application special is the fact that it was written for Android.
Assumptions:
- remote control (Bluetooth)
- you can change the color of light (RGB LEDs)
- „emergency” control by four buttons: R – red, G – green, B – blue and M – mode)
Software:
Program was made in Eclipse environment using Java. It was written for Android 4.0.3 version. You have to rememeber to enter the MAC address of your own Bluetooth module. Program for a cell phone in its initial version had only three sliders, separately one for each color. It was extended with a „color picker”, 10 additional favourite colours and selecting the time, after which the light turns off. In addition, there are two buttons for turning on and off the light and activation of rainbow mode.
Values of each color are stored after each change, so when the application is started again, everything stays the same, as if you never closed it. The only exception is timer, values of which are not stored.
The application (main screen and color selection using the „picker”):
Hardware:
Arduino was chosen because it is easy to program and user-friendly.
31 RGB diodes are connected in parallel. Total load is quite significant, so Arduino theoretically could not manage to turn on 31 diodes simultaneously. That is why each color is turned on separately by a transistor BD139.
Bluetooth module used in this project operates in logic 3,3V, so the device required a voltage regulator and MAX3232. Signal from BT module is inverted, so you also need an inverter. Base for mounting the LEDs was made of an empty plastic bottle. You have to cut three rings and make holes for the LEDs. Everything soldered together should form a compact design.
Housing was made of elements of a cheap lamp adapted for this purpose. Adhesive tape visible in pictures blocks the light of small LEDs of Arduino and BT module.
Everything is on universal boards, but you can use more professional boards as well.
Here are pictures of the system on mega8:
Firmware:
Writing program for Arduino can start with Bluetooth support. Then you can add the other functions.
List of components:
- Arduino nano
- BTM5 – Bluetooth module
- 31 RGB diodes
- 63 resistors for the diodes (150-220R)
- 7400 nand gates operating as inverters
- MAX3232 – TTL-RS232 converter
- 3,3V regulator
- 3x BD139
- 8x 100nF
- 4x switch
- 4x 10k resistor
- 2x jumper (for disconnecting RX TX line, so you can program Arduino in the system)
- 5V/2A power supply
- lamp
Link to original thread (useful attachment) - YAALL - czyli jeszcze jedna LED'owa lampa Arduino
