espressif/extended_vfs - 0.3.1 - Example i2c_tt21100 • ESP Component Registry

I2C TT21100 Example

This example shows how to configure I2C bus and read data from TT21100(touch pad) by POSIX APIs, this decreases dependence on hardware and platform.

How to Use Example

Before project configuration and build, be sure to set the correct chip target using idf.py set-target <chip_name>.

Hardware Required

A development board based on espressif SoC
A USB cable for power supply and programming
A TT21100 connecting to your configured GPIO, Power and GND, if your development board doesn't integrate TT21100

Configure the Project

Open the project configuration menu (idf.py menuconfig).

In the Example Configuration menu:

Set the I2C GPIO number used for the signal in the following option:
- I2C SDA Pin Number
- I2C SCL Pin Number
- TT21100 Ready Pin Number
Set the reading sensor data count in the I2C Testing Count of Reading Sensor's Data option.

Build and Flash

Run idf.py -p PORT flash monitor to build, flash and monitor the project.

(To exit the serial monitor, type Ctrl-].)

Example Output

As you run the example, you will see following log:

Plaintext

I (0) cpu_start: Starting scheduler on APP CPU.
I (315) ext_vfs: Extended VFS version: 0.1.0
I (315) gpio: GPIO[3]| InputEn: 1| OutputEn: 0| OpenDrain: 0| Pullup: 0| Pulldown: 0| Intr:0 
TT21100 touch screen is initialized, and start reading touch point information:

Then you can touch the TT21100 touch pad and see touch point location information as following:

Plaintext

  X0=122 Y0=146
  X0=122 Y0=146
  X0=122 Y0=146
  X0=122 Y0=146
  X0=122 Y0=146
  X0=122 Y0=146
  X0=152 Y0=169
  X0=152 Y0=169
  X0=152 Y0=169
  X0=152 Y0=169
  X0=152 Y0=169
  X0=152 Y0=169
  X0=153 Y0=169
  X0=153 Y0=169
  X0=217 Y0=170
  X0=217 Y0=170
  X0=219 Y0=170
  X0=220 Y0=170
  X0=221 Y0=169
  X0=221 Y0=169
  X0=217 Y0=168
  X0=217 Y0=168
  X0=106 Y0=186
  X0=106 Y0=186
  X0=106 Y0=186
  X0=106 Y0=186
  X0=106 Y0=186
  X0=106 Y0=186
  X0=106 Y0=186
  X0=106 Y0=186
  X0=68 Y0=173
  X0=68 Y0=173
  X0=68 Y0=173
  X0=67 Y0=173
  X0=67 Y0=173
  X0=66 Y0=171
  X0=65 Y0=166
  X0=65 Y0=166
  X0=95 Y0=106
  X0=95 Y0=106
  X0=95 Y0=106
  X0=95 Y0=106
  X0=94 Y0=106
  X0=93 Y0=106
  X0=93 Y0=106
  X0=93 Y0=106
  X0=91 Y0=79
  X0=91 Y0=79
  X0=91 Y0=79
  X0=90 Y0=79
  X0=87 Y0=80
  X0=84 Y0=82
  X0=82 Y0=84
  X0=80 Y0=85
  X0=80 Y0=85
  X0=54 Y0=106
  X0=54 Y0=106
  X0=54 Y0=106
  X0=53 Y0=108
  X0=52 Y0=110
  X0=50 Y0=111
  X0=50 Y0=112
  X0=49 Y0=112
  X0=49 Y0=112
  X0=48 Y0=141
  X0=48 Y0=141
  X0=48 Y0=141
  X0=47 Y0=141
  X0=47 Y0=141
  X0=46 Y0=141
  X0=45 Y0=141
  X0=45 Y0=141
  X0=67 Y0=152
  X0=67 Y0=152
  X0=67 Y0=152
  X0=67 Y0=152
  X0=67 Y0=152
  X0=67 Y0=152
  X0=66 Y0=152
  X0=66 Y0=152
  X0=78 Y0=165
  X0=78 Y0=165
  X0=78 Y0=164
  X0=78 Y0=164
  X0=78 Y0=163
  X0=79 Y0=163
  X0=79 Y0=162
  X0=79 Y0=162
  X0=140 Y0=139
  X0=140 Y0=139
  X0=140 Y0=139
  X0=140 Y0=139
  X0=140 Y0=139
  X0=141 Y0=138
  X0=142 Y0=137
  X0=144 Y0=134
  X0=144 Y0=134
  X0=178 Y0=128
  X0=178 Y0=128
  X0=178 Y0=128
I (4145) gpio: GPIO[3]| InputEn: 0| OutputEn: 0| OpenDrain: 0| Pullup: 0| Pulldown: 0| Intr:0 
Test done and de-initialize TT21100 touch screen.