KS0210 keyestudio RPI TTP229L 16-key Capacitive Touch Keypad

1. Introduction

This keypad is designed for Raspberry Pi and supplies your Pi with 16 keys. It has an I2C communication mode and uses 3.3 V supply voltage with a power indicator.

We provide you with installation package, source codes and a document to help you complete your programs.

2. Specification

  • Chip: TTP229-LSF

  • Supply Voltage: 3.3V

  • Interface: I2C

3. Shipping List

  • keyestudio RPI TTP229L 16-key Capacitive Touch Keypad x1

  • M2.5*6MM screw x 6

  • M2.5*19MM copper pillar x 3

4. Connection Diagram

Plug it directly into Raspberry Pi to start your works as shown in below figure.

After power-on have about 0.5sec stable-time. During the time do not touch the key pad, and all functions are disabled.

5. Sample Code

Download Resources : Resources

#include <bcm2835.h>  
#include <stdio.h>
#include <unistd.h>
unsigned char WriteBuf;
unsigned char WriteBuf1;  
unsigned int ReadBuf0;  

int main(int argc, char **argv)  
{  
    if (!bcm2835_init())  
    return 1;  
    bcm2835_i2c_begin();  
    bcm2835_i2c_setSlaveAddress(0x57);  
    bcm2835_i2c_set_baudrate(10000);  
    printf("start..........\n"); 

    while(1)  
    {  
		WriteBuf = 0x00;  
		bcm2835_i2c_write_read_rs(&WriteBuf,2,&WriteBuf1,2);  
		bcm2835_i2c_read (&ReadBuf0,2);        
		printf("TTP229:%d\n",ReadBuf0);
		printf ("\r");
		fflush (stdout);
		bcm2835_delay(100);  
    }   
    bcm2835_i2c_end();  
    bcm2835_close();  
    return 0;  
}

6. Program Writing

1.Installing bcm-2835 Library

Here is the tutorial for installing bcm-2835 library in Raspberry Pi. To install bcm-2835, first we need to download bcm2835 library.

Step1: Now after downloading library, copy it in any folder of your raspberry pi by winSCP(we provide its installation package, but please refer to usage by yourselves).

Step2: Now it’s time to extract the library, so open terminal of raspberry pi and go to the folder where you have copied your library and type this command: tar zxvf bcm2835-1.39.tar.gz

Step3: Now to into library folder, type this command: cd bcm2835-1.39

Step4: Now, we are ready to install bcm2835 library, so to start installation type this command: ./configure

Step5: then type this command: make

Step6: then this: sudo make check

**Step7:**and finally this: sudo make install

Congrats your library is installed. Now use “#include <bcm2835.h>” in your program to use bcm2835 library.

2.Programming

Now it’s time to write a program. If you need to create a new directory within raspberry pi, you can use the ‘mkdir’ command. So type at your terminal: mkdir rpi_shield.

Then copy the file rpi_TTP229L provided by us and put it into the directory rpi_shield through winSCP. Next, type this command: cd rpi_TTP229L to go inside the rpi_TTP229L folder.

Then type this command: make to make an executable file; This means this is the file we run to launch the program as shown in below figure.

To make a new directory, you just need to add the name of the directory after the command, such as ‘mkdir new_directory’.

Finally type this: sudo ./TTP229 to launch the program.

image-20260113111803668

7. Result

Touch the keys, and corresponding value is printed on the terminal as shown in below figure. Use Ctrl+C to exit the processing program.

sudo ./TTP229 to running program

Touching different keys to print various value.