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https://github.com/DarkFlippers/unleashed-firmware
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45 lines
1.4 KiB
Markdown
45 lines
1.4 KiB
Markdown
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# 1-Wire Thermometer
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This example application demonstrates the use of the 1-Wire library with a DS18B20 thermometer.
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It also covers basic GUI, input handling, threads and localisation.
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## Electrical connections
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Before launching the application, connect the sensor to Flipper's external GPIO according to the table below:
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| DS18B20 | Flipper |
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| :-----: | :-----: |
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| VDD | 9 |
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| GND | 18 |
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| DQ | 17 |
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*NOTE 1*: GND is also available on pins 8 and 11.
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*NOTE 2*: For any other pin than 17, connect an external 4.7k pull-up resistor to pin 9.
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## Launching the application
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In order to launch this demo, follow the steps below:
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1. Make sure your Flipper has an SD card installed.
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2. Connect your Flipper to the computer via a USB cable.
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3. Run `./fbt launch_app APPSRC=example_thermo` in your terminal emulator of choice.
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## Changing the data pin
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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:
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```c
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/* Possible GPIO pin choices:
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- gpio_ext_pc0
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- gpio_ext_pc1
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- gpio_ext_pc3
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- gpio_ext_pb2
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- gpio_ext_pb3
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- gpio_ext_pa4
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- gpio_ext_pa6
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- gpio_ext_pa7
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- ibutton_gpio
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*/
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#define THERMO_GPIO_PIN (ibutton_gpio)
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```
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Do not forget about the external pull-up resistor as these pins do not have one built-in.
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With the changes been made, recompile and launch the application again.
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The on-screen text should reflect it by asking to connect the thermometer to another pin.
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