(visit http://store.nkcelectronics.com/rgb-lcd-shield-for-arduino-65k-color-k65.html to purchase)
The LCD module has a backlight made of 2 white LEDs that requiere approximate 9V with a max 19mA current to work. As this voltage level is not available on the Arduino board, I used an ST232 RS232 driver to get 8V DC from the standard 5V Arduino power supply. The backlight driver circuit now included in the main RGB LCD shield PCB.
It contains the following components:
1 x RGB LCD module
1 x RGB LCD shield PCB
1 x LCD module to PCB soldering adapter
1 x LM317T variable voltage regulator
2 x 10uF electrolytic capacitors
5 x 0.1uF ceramic capacitors
1 x 330 ohm resistor
1 x 430 ohm resistor
5 x 1Kohm resistors
5 x 1.3Kohm (1K3) resistors
1 x 28-pin male breakable header (you need to cut 2 8-pin sections, 2 6-pin sections)
1 x ST232 RS232 driver IC
1 x 110 ohm resistor
Step 1: Mounting the Adapter Pads on LCD
Let’s start with the main RGB LCD shield PCB. The LCD module needs to be soldered first. Separate the LCD module and a small green thin PCB used to attach the LCD module to the main black PCB.
Apply some solder in one of the pins of the LCD module, you can choose either pin 1 or pin 10 (pin 1 is the one to the right of the picture).
Once the solder is applied, place the small thin PCB and align the 10 pads to the 10 pads on the LCD module. Heat the pin that has the solder to attach the small thin PCB (the adapter). Once you are satisfied how it is aligned (make sure the pads are correctly aligned, to avoid shorting the pins), solder the rest of the pads.
Step 2: Soldering LCD to Main PCB
The LCD part is done. We need to check for any short circuits before advancing in the assembly process.
Step 3: Soldering the Headers
Solder the pin headers and plug it into the Arduino (Freeduino, Seeeduino, *duino) board to check it is not causing any short to the main board.
Step 4: Working on the Power Supply
Solder first the LM317 voltage regulator. Then you can solder the 0.1uF ceramic capacitors C2 and C3. Orientation is not important for the ceramic capacitors. Then solder the 10uF electrolytic capacitor, negative leg to the left, positive (long) to the right. Next you need to solder R12 430 ohm resistor (you can follow the guide in http://www.bpesolutions.com/atechnical/ResistorQV.pdf to calculate the resistor colors). 430 ohms is yellow, orange, brown. Then solder R13 330 ohm resistor (orange, orange, brown). The power supply section is complete.
Step 5: Voltage Check
And make sure you get 2.9V from the voltage regulator following the next 2 pictures…
Step 6: Assemble Voltage Dividers
Step 7: Assemble Step-up Circuit
Step 8: Testing and Enjoying!
The sample code is self explanatory (You don’t need to mess with the setup code, just look for the piece of code that sends the characters to the screen, how the dots are turned on and off, etc. I created 2 codes, one using digitalWrite() and another one using direct AVR I/O… I found the 2nd method to be almost 10 times faster, and drawing things on the screen, you can notice the difference in speed.
The sample codes are here:
Sample using digitalWrite()
Sample using direct AVR I/O
Click on the source code and copy the contento to Arduino, or download the .txt files and rename them as .pde