Embedded Touch Sensor

Introduction

With this project we will manage a Touch Sensor (Tontek TTP223-BA6), using the FTDI FT232H development board (of which there is a dedicated page on this site).

Connection

This Touch sensor must be connected to the FTDI FT232H development board. The connection connectors are listed below:

Python code

To manage this Touch Sensor, the presence of the "PyFTDI" library is required.
The following Python code example displays if touch on Touch Sensor is detected:

from os import environ
from pyftdi.gpio import GpioAsyncController
import time

_ctrl = GpioAsyncController()
url = environ.get('FTDI_DEVICE', 'ftdi:///1')
_ctrl.configure(url, direction=0b0, frequency=None, initial=0x0)
_gpio = _ctrl.get_gpio()
print("GPIO.pins = ", _gpio.pins, "(", bin(_gpio.pins), ")")
print("GPIO.all_pins = ", bin(_gpio.all_pins))
print("GPIO.width = ", _gpio.width)
direction = _gpio.direction
print("GPIO.direction (Old) = ", bin(direction))
_gpio.set_direction(0b1, 0b0)
print("GPIO.direction (New) = ", bin(_gpio.direction))
tmp = 0

try:
    while True:
       pins = _gpio.read()
       pins &= ~0xfe
       if pins != tmp:
          if pins == 0:
             print('* Sensor = untouched *')
          if pins == 1:
             print('* Sensor = touched   *')
          tmp = pins
          time.sleep(0.25)
    """Close the connection"""
except KeyboardInterrupt:
    # Capture keyboard ^C to exit the program
    print('\nYou terminated the program. The program ends!')
    _ctrl.close()