diff --git a/docs/docs/config/kscan.md b/docs/docs/config/kscan.md index ac773f18..984fd6ac 100644 --- a/docs/docs/config/kscan.md +++ b/docs/docs/config/kscan.md @@ -281,7 +281,70 @@ Definition file: [zmk/app/dts/bindings/zmk,matrix-transform.yaml](https://github The `map` array should be defined using the `RC()` macro from [dt-bindings/zmk/matrix_transform.h](https://github.com/zmkfirmware/zmk/blob/main/app/include/dt-bindings/zmk/matrix_transform.h). It should have one item per logical position in the keymap. Each item should list the physical row and column that should trigger the key in that position. -### Example Configuration +### Example: Skipping Unused Positions + +Any keyboard which is not a grid of 1 unit keys will likely have some unused positions in the matrix. A matrix transform can be used to skip the unused positions so users don't have to set them to `&none` in keymaps. + +```devicetree +// numpad.overlay +/ { + chosen { + zmk,kscan = &kscan0; + zmk,matrix_transform = &default_transform; + }; + + kscan0: kscan { + compatible = "zmk,kscan-gpio-matrix"; + rows = <5>; + columns = <4>; + // define the matrix... + }; + + default_transform: matrix_transform { + compatible = "zmk,matrix-transform"; + rows = <5>; + columns = <4>; + // ┌───┬───┬───┬───┐ + // │NUM│ / │ * │ - │ + // ├───┼───┼───┼───┤ + // │ 7 │ 8 │ 9 │ + │ + // ├───┼───┼───┤ │ + // │ 4 │ 5 │ 6 │ │ + // ├───┼───┼───┼───┤ + // │ 1 │ 2 │ 3 │RET│ + // ├───┴───┼───┤ │ + // │ 0 │ . │ │ + // └───────┴───┴───┘ + map = < + RC(0,0) RC(0,1) RC(0,2) RC(0,3) + RC(1,0) RC(1,1) RC(1,2) RC(1,3) + RC(2,0) RC(2,1) RC(2,2) + RC(3,0) RC(3,1) RC(3,2) RC(3,3) + RC(4,0) RC(4,1) + >; + }; +}; +``` + +```devicetree +// numpad.keymap +/ { + keymap { + compatible = "zmk,keymap"; + default { + bindings = < + &kp KP_NUM &kp KP_DIV &kp KP_MULT &kp KP_MINUS + &kp KP_N7 &kp KP_N8 &kp KP_N9 &kp KP_PLUS + &kp KP_N4 &kp KP_N5 &kp KP_N6 + &kp KP_N1 &kp KP_N2 &kp KP_N3 &kp KP_ENTER + &kp KP_N0 &kp KP_DOT + >; + }; + } +}; +``` + +### Example: Non-standard Matrix Consider a keyboard with a [duplex matrix](https://wiki.ai03.com/books/pcb-design/page/matrices-and-duplex-matrix), where the matrix has twice as many rows and half as many columns as the keyboard has keys. A matrix transform can be used to correct for this so that keymaps can match the layout of the keys, not the layout of the matrix.