diff --git a/docs/docs/features/underglow.md b/docs/docs/features/underglow.md index 3692a6de..a093ecac 100644 --- a/docs/docs/features/underglow.md +++ b/docs/docs/features/underglow.md @@ -55,10 +55,16 @@ If you have a shield with RGB underglow, you must add a `boards/` directory with Inside the `boards/` folder, you define a `.overlay` for each different board. For example, the Kyria shield has a `boards/nice_nano.overlay` file that defines the RGB underglow for the `nice_nano` board specifically. -The first step to adding support for underglow is to select you SPI output. With nRF52 boards, you can just use `&spi1` and define the pins you want to use. -For other boards, you must select an SPI definition that has the `MOSI` pin as your data pin going to your LED strip. +### nRF52-based boards + +With nRF52 boards, you can just use `&spi1` and define the pins you want to use. + +To identify which pin number you need to put in the config you need do to a bit of math. You need the hardware port and run it through a function. +**32 \* X + Y** = `` where X is first part of the hardware port "PX.01" and Y is the second part of the hardware port "P1.Y". + +(_P1.13_ would give you _32 \* 1 + 13_ = `<45>` and P0.15 would give you _32 \* 0 + 15_ = `<15>`) -Here's an example of an nRF52 SPI definition: +Here's an example on a definition that uses P0.06: ``` &spi1 { @@ -87,11 +93,15 @@ Here's an example of an nRF52 SPI definition: :::info -If you are configuring SPI for an nRF52840 (or other nRF52) based board, double check that you are using pins that aren't restricted to low frequency I/O. -Ignoring these restrictions may result in poor wireless performance. You can find the list of low frequency I/O pins [here](https://infocenter.nordicsemi.com/index.jsp?topic=%2Fps_nrf52840%2Fpin.html&cp=4_0_0_6_0). +If you are configuring SPI for an nRF52 based board, double check that you are using pins that aren't restricted to low frequency I/O. +Ignoring these restrictions may result in poor wireless performance. You can find the list of low frequency I/O pins for the nRF52840 [here](https://infocenter.nordicsemi.com/index.jsp?topic=%2Fps_nrf52840%2Fpin.html&cp=4_0_0_6_0). ::: +### Other boards + +For other boards, you must select an SPI definition that has the `MOSI` pin as your data pin going to your LED strip. + Here's another example for a non-nRF52 board on `spi1`: ```