8672a1d94c
strlcpy doesn't zero the buffer and ensures null termination, just like snprintf strlcat is already used by mjs and it's a safe alternative to strcat, so it should be OK to expose to apps |
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| .. | ||
| application.fam | ||
| example_thermo.c | ||
| example_thermo_10px.png | ||
| README.md | ||
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.
Source code
Source code for this example can be found here.
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:
- Make sure your Flipper has an SD card installed.
- Connect your Flipper to the computer via a USB cable.
- Run
./fbt launch APPSRC=example_thermoin 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.