unleashed-firmware/applications/examples/example_thermo

1-Wire Thermometer

This example application demonstrates the use of the 1-Wire library with a DS18B20 thermometer. It also covers basic GUI, input handling, threads and localisation.

Electrical connections

Before launching the application, connect the sensor to Flipper's external GPIO according to the table below:

DS18B20	Flipper
VDD	9
GND	18
DQ	17

NOTE 1: GND is also available on pins 8 and 11.

NOTE 2: For any other pin than 17, connect an external 4.7k pull-up resistor to pin 9.

Launching the application

In order to launch this demo, follow the steps below:

1. Make sure your Flipper has an SD card installed.
2. Connect your Flipper to the computer via a USB cable.
3. Run ./fbt launch APPSRC=example_thermo in your terminal emulator of choice.

Changing the data pin

It is possible to use other GPIO pin as a 1-Wire data pin. In order to change it, set the THERMO_GPIO_PIN macro to any of the options listed below:

/* Possible GPIO pin choices:
 - gpio_ext_pc0
 - gpio_ext_pc1
 - gpio_ext_pc3
 - gpio_ext_pb2
 - gpio_ext_pb3
 - gpio_ext_pa4
 - gpio_ext_pa6
 - gpio_ext_pa7
 - gpio_ibutton
*/

#define THERMO_GPIO_PIN (gpio_ibutton)

Do not forget about the external pull-up resistor as these pins do not have one built-in.

With the changes been made, recompile and launch the application again. The on-screen text should reflect it by asking to connect the thermometer to another pin.