Thursday, December 16, 2010

LCD Tips and Tricks

Liquid Crystal Display (LCD) is widely used today. For beginners to begin experimenting, circuit as shown below can be constructed.
Schematics for LCD From the diagram above, we can see that extra circuit is required before any input is available to the Enable(E) pin of the LCD. This circuit is actually a debounce circuit built from two NAND gate logic. If this debounce circuit is not addded, then, what will happens is that, whenever the input changes from logic 1 to logic 0 at the Enable pin while PS pin is logic 1, the LCD will display the predefined character from D7D6D5…D2D1D0. By allowing debouncing on E pin to occur, the LCD will display multiple of the first character until the switch is stable. Below is the table that defines the characters that the LCD can display with the equivalent binary codes.
LCD character mapingIn order to command the LCD to do a specific task, command code is needed. Thus, the following table will show the tasks with the equivalent hex code:
lcd command
To begin,
  1. Set E, RW, RS to 0.
  2. Set D7D6D5…D2D1D0 to 0001111.
  3. Set E to 1.
  4. Set D7D6D5…D2D1D0 to 0000000.
  5. Set RS to 1.
  6. Set the appropriate letter to be displayed on D7D6D5…D2D1D0.
  7. Set E to 1 to display. Then, Set E back to 0.
  8. Continue the above steps until message is displayed.

Wednesday, August 4, 2010

Generating Eagle PCB in 3D

POVRAY 3D PCB

POVRay 3D can be used in cooperate with Eagle PCB to generate a 3D view of the PCB that we have designed. This will give us a better look on the PCB and component layout before we finalized the PCB for fabrication.

To use POV-ray:

  1. Click Tools -> Edit master POVRAY.INI

  2. A notepad file should load up. At the very bottom of it, add this line:

  3. Library_Path="C:\Program Files\Eagle3D\povray" (depending on where you install the file)

  4. Press on Render button in POV-ray

  5. You should get the 3D view of your PCB. Cheers ~~

Sunday, May 23, 2010

LCD Tips n' Tricks

Liquid Crystal Display (LCD) is widely used today. For beginners to begin experimenting, circuit as shown below can be constructed.

From the diagram above, we can see that extra circuit is required before any input is available to the Enable(E) pin of the LCD. This circuit is actually a debounce circuit built from two NAND gate logic. If this debounce circuit is not addded, then, what will happens is that, whenever the input changes from logic 1 to logic 0 at the Enable pin while PS pin is logic 1, the LCD will display the predefined character from D7D6D5...D2D1D0. By allowing debouncing on E pin to occur, the LCD will display multiple of the first character until the switch is stable. Below is the table that defines the characters that the LCD can display with the equivalent binary codes.

In order to command the LCD to do a specific task, command code is needed. Thus, the following table will show the tasks with the equivalent hex code:



To begin,

  1. Set E, RW, RS to 0.

  2. Set D7D6D5...D2D1D0 to 0001111.

  3. Set E to 1.

  4. Set D7D6D5...D2D1D0 to 0000000.

  5. Set RS to 1.

  6. Set the appropriate letter to be displayed on D7D6D5...D2D1D0.

  7. Set E to 1 to display. Then, Set E back to 0.

  8. Continue the above steps until message is displayed.