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Improve port/pin docs, fix punctuation

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ReFil 2023-08-15 09:19:04 +01:00
parent 1e092ff296
commit ca8049461d
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26
docs/docs/features/backlight.md
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@ -91,7 +91,7 @@ Then you have to add the following lines inside the root devicetree node on the
The value inside `pwm_led_0` must be the same as you used before.
In this example `10000` is the period of the PWM waveform, some drive circuitry might require different values, it could also be altered in the event the drive frequency is audible/
In this example `10000` is the period of the PWM waveform, some drive circuitry might require different values, it could also be altered in the event the drive frequency is audible.
If your board uses a P-channel MOSFET to control backlight instead of a N-channel MOSFET, you may want to change `PWM_POLARITY_NORMAL` for `PWM_POLARITY_INVERTED`.
@ -140,19 +140,16 @@ A pinctrl file has an `&pinctrl` node that encompasses all pinctrl settings incl
};
pwm0_sleep: pwm0_sleep {
group1 {
psels = <NRF_PSEL(PWM_OUT0, 0, 45)>;
psels = <NRF_PSEL(PWM_OUT0, 1, 13)>;
low-power-enable;
};
};
}
```
The pin number is calculated in the same way as for the non pinctrl configuration.
The pin number is handled differently depending on the MCU in question, on nRF boards it is defined as (PWM_OUTX, Y, Z) where X is the PWM channel used (usually 0) Y is first part of the hardware port "PY.01" and Z is the second part of the hardware port "P1.Z".
The value `45` in the example represents the pin that controls the LEDs. With nRF52 boards, you can calculate the value to use in the following way: you need the hardware port and run it through a function.
**32 \* X + Y** = `<Pin number>` where X is first part of the hardware port "PX.01" and Y is the second part of the hardware port "P1.Y".
For example, _P1.13_ would give you _32 \* 1 + 13_ = `<PWM_OUT0, 0, 45>` and _P0.15_ would give you _32 \* 0 + 15_ = `<PWM_OUT0, 0, 15>`.
For example, _P1.13_ would give you `(PWM_OUT0, 1, 13)` and _P0.15_ would give you `(PWM_OUT0, 0, 15)`.
Then you add the PWM device inside the `board.dts` file and assign the pinctrl definitions to it
@ -178,7 +175,7 @@ Then you have to add the following lines inside the root devicetree node on the
};
```
In this example `10000` is the period of the PWM waveform, some drive circuitry might require different values, it could also be altered in the event the drive frequency is audible/
In this example `10000` is the period of the PWM waveform, some drive circuitry might require different values, it could also be altered in the event the drive frequency is audible.
If your board uses a P-channel MOSFET to control backlight instead of a N-channel MOSFET, you may want to change `PWM_POLARITY_NORMAL` for `PWM_POLARITY_INVERTED`.
@ -305,24 +302,21 @@ Then add the following lines to your `.overlay` file:
// Other pinctrl definitions for other hardware
pwm0_default: pwm0_default {
group1 {
psels = <NRF_PSEL(PWM_OUT0, 0, 45)>;
psels = <NRF_PSEL(PWM_OUT0, 1, 13)>;
};
};
pwm0_sleep: pwm0_sleep {
group1 {
psels = <NRF_PSEL(PWM_OUT0, 0, 45)>;
psels = <NRF_PSEL(PWM_OUT0, 1, 13)>;
low-power-enable;
};
};
}
```
The pin number is calculated in the same way as for the non pinctrl configuration.
The pin number is handled differently depending on the MCU in question, on nRF boards it is defined as (PWM_OUTX, Y, Z) where X is the PWM channel used (usually 0) Y is first part of the hardware port "PY.01" and Z is the second part of the hardware port "P1.Z".
The value `45` in the example represents the pin that controls the LEDs. With nRF52 boards, you can calculate the value to use in the following way: you need the hardware port and run it through a function.
**32 \* X + Y** = `<Pin number>` where X is first part of the hardware port "PX.01" and Y is the second part of the hardware port "P1.Y".
For example, _P1.13_ would give you _32 \* 1 + 13_ = `<PWM_OUT0, 0, 45>` and _P0.15_ would give you _32 \* 0 + 15_ = `<PWM_OUT0, 0, 15>`.
For example, _P1.13_ would give you `(PWM_OUT0, 1, 13)` and _P0.15_ would give you `(PWM_OUT0, 0, 15)`.
Then you add the PWM device inside the `.overlay` file and assign the pinctrl definitions to it
@ -348,7 +342,7 @@ Then you have to add the following lines inside the root devicetree node on the
};
```
In this example `10000` is the period of the PWM waveform, some drive circuitry might require different values, it could also be altered in the event the drive frequency is audible/
In this example `10000` is the period of the PWM waveform, some drive circuitry might require different values, it could also be altered in the event the drive frequency is audible.
If your board uses a P-channel MOSFET to control backlight instead of a N-channel MOSFET, you may want to change `PWM_POLARITY_NORMAL` for `PWM_POLARITY_INVERTED`.