Character LCD with 4 Data Bits

Overview

I came across this on the Cypress Forums. It is a great tool for reducing pins usage. The original example was made for PSoC 5 and 3. I tried it on PSoC 4 and it worked perfectly.

This design requires a custom component block in order to work. For reference, the schematic wiring is included. When opening the program, you will be prompted about this custom component. Just say: YES.

Pin Connections

Notice that the only pins that are wired from pins are RS, E, D4 - D7.

To add this custom component to a new project, go to the components tab in the Workspace Explorer.

Right click on the Project item and choose Import Component.

Importing Components

You can import the component from a project or an archive.

Just look for the file and select the desired component (you will find them in the project folder of the attached workspace).

For the example, I added the External LCD and the CharLCDmp v1.1, but you only need the CharLCD for this to work.

Then you will find it here:

And just use it like any other block.

The code is the same as in any other LCD block:

#include <device.h> 
#define clr() LCD_ClearDisplay(); 
int main(){	      
   CyGlobalIntEnable; 
   clr();   
   LCD_Start(); clr();      
   LCD_Position(0u, 0u); LCD_PrintString("LCD with 4bits");     
   LCD_Position(1u, 0u);LCD_PrintString("Cypress PSOC 4"); 
   for(;;){  
   } 
}