From 26eef35f07698d23aafae90e1c230b52e100a334 Mon Sep 17 00:00:00 2001 From: James Young Date: Sat, 29 Feb 2020 12:00:00 -0800 Subject: 2020 February 29 Breaking Changes Update (#8064) --- docs/feature_backlight.md | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) (limited to 'docs/feature_backlight.md') diff --git a/docs/feature_backlight.md b/docs/feature_backlight.md index e74aab1e37..7c68d74e1c 100644 --- a/docs/feature_backlight.md +++ b/docs/feature_backlight.md @@ -119,10 +119,22 @@ When both timers are in use for Audio, the backlight PWM will not use a hardware To change the behavior of the backlighting, `#define` these in your `config.h`: -|Define |Default |Description | -|---------------------|-------------|--------------------------------------------------------------------------------------------------------------| -|`BACKLIGHT_PIN` |`B7` |The pin that controls the LEDs. Unless you are designing your own keyboard, you shouldn't need to change this | -|`BACKLIGHT_PINS` |*Not defined*|experimental: see below for more information | +|Define |Default |Description | +|---------------------|-------------|-------------------------------------------------------------------------------------------------------------| +|`BACKLIGHT_PIN` |`B7` |The pin that controls the LEDs. Unless you are designing your own keyboard, you shouldn't need to change this| +|`BACKLIGHT_PINS` |*Not defined*|experimental: see below for more information | +|`BACKLIGHT_LEVELS` |`3` |The number of brightness levels (maximum 31 excluding off) | +|`BACKLIGHT_CAPS_LOCK`|*Not defined*|Enable Caps Lock indicator using backlight (for keyboards without dedicated LED) | +|`BACKLIGHT_BREATHING`|*Not defined*|Enable backlight breathing, if supported | +|`BREATHING_PERIOD` |`6` |The length of one backlight "breath" in seconds | +|`BACKLIGHT_ON_STATE` |`1` |The state of the backlight pin when the backlight is "on" - `1` for high, `0` for low | + +### Backlight On State + +Most backlight circuits are driven by an N-channel MOSFET or NPN transistor. This means that to turn the transistor *on* and light the LEDs, you must drive the backlight pin, connected to the gate or base, *high*. +Sometimes, however, a P-channel MOSFET, or a PNP transistor is used. In this case, when the transistor is on, the pin is driven *low* instead. + +This functionality is configured at the keyboard level with the `BACKLIGHT_ON_STATE` define. ### Multiple backlight pins -- cgit v1.2.3