led: Add support for PWM controlled LEDs

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

2 files changed, 99 insertions, 75 deletions

diff --git a/docs/Config_Reference.md b/docs/Config_Reference.md
index 7fca3797..d8096a6f 100644
--- a/docs/Config_Reference.md
+++ b/docs/Config_Reference.md
@@ -2505,45 +2505,44 @@ with the SET_FAN_SPEED [gcode command](G-Codes.md#fan_generic).
 #   See the "fan" section for a description of the above parameters.
 ```
 
-## Additional servos, LEDs, buttons, and other pins
+## LEDs
 
-### [servo]
+### [led]
 
-Servos (one may define any number of sections with a "servo"
-prefix). The servos may be controlled using the SET_SERVO
-[g-code command](G-Codes.md#servo). For example: SET_SERVO
-SERVO=my_servo ANGLE=180
+Support for LEDs (and LED strips) controlled via micro-controller PWM
+pins (one may define any number of sections with an "led" prefix). See
+the [command reference](G-Codes.md#led) for more information.
 
 ```
-[servo my_servo]
-pin:
-#   PWM output pin controlling the servo. This parameter must be
-#   provided.
-#maximum_servo_angle: 180
-#   The maximum angle (in degrees) that this servo can be set to. The
-#   default is 180 degrees.
-#minimum_pulse_width: 0.001
-#   The minimum pulse width time (in seconds). This should correspond
-#   with an angle of 0 degrees. The default is 0.001 seconds.
-#maximum_pulse_width: 0.002
-#   The maximum pulse width time (in seconds). This should correspond
-#   with an angle of maximum_servo_angle. The default is 0.002
-#   seconds.
-#initial_angle:
-#   Initial angle (in degrees) to set the servo to. The default is to
-#   not send any signal at startup.
-#initial_pulse_width:
-#   Initial pulse width time (in seconds) to set the servo to. (This
-#   is only valid if initial_angle is not set.) The default is to not
-#   send any signal at startup.
+[led my_led]
+#red_pin:
+#green_pin:
+#blue_pin:
+#white_pin:
+#   The pin controlling the given LED color. At least one of the above
+#   parameters must be provided.
+#cycle_time: 0.010
+#   The amount of time (in seconds) per PWM cycle. It is recommended
+#   this be 10 milliseconds or greater when using software based PWM.
+#   The default is 0.010 seconds.
+#hardware_pwm: False
+#   Enable this to use hardware PWM instead of software PWM. When
+#   using hardware PWM the actual cycle time is constrained by the
+#   implementation and may be significantly different than the
+#   requested cycle_time. The default is False.
+#initial_RED: 0.0
+#initial_GREEN: 0.0
+#initial_BLUE: 0.0
+#initial_WHITE: 0.0
+#   Sets the initial LED color. Each value should be between 0.0 and
+#   1.0. The default for each color is 0.
 ```
 
 ### [neopixel]
 
 Neopixel (aka WS2812) LED support (one may define any number of
-sections with a "neopixel" prefix). One may set the LED color via
-"SET_LED LED=my_neopixel RED=0.1 GREEN=0.1 BLUE=0.1" type extended
-[g-code commands](G-Codes.md#neopixel).
+sections with a "neopixel" prefix). See the
+[command reference](G-Codes.md#led) for more information.
 
 ```
 [neopixel my_neopixel]
@@ -2561,17 +2560,14 @@ pin:
 #initial_GREEN: 0.0
 #initial_BLUE: 0.0
 #initial_WHITE: 0.0
-#   Sets the initial LED color of the Neopixel. Each value should be
-#   between 0.0 and 1.0. The WHITE option is only available on RGBW
-#   LEDs. The default for each color is 0.
+#   See the "led" section for information on these parameters.
 ```
 
 ### [dotstar]
 
 Dotstar (aka APA102) LED support (one may define any number of
-sections with a "dotstar" prefix). One may set the LED color via
-"SET_LED LED=my_dotstar RED=0.1 GREEN=0.1 BLUE=0.1" type extended
-[g-code commands](G-Codes.md#neopixel).
+sections with a "dotstar" prefix). See the
+[command reference](G-Codes.md#led) for more information.
 
 ```
 [dotstar my_dotstar]
@@ -2582,13 +2578,14 @@ clock_pin:
 #   The pin connected to the clock line of the dotstar. This parameter
 #   must be provided.
 #chain_count:
+#   See the "neopixel" section for information on this parameter.
 #initial_RED: 0.0
 #initial_GREEN: 0.0
 #initial_BLUE: 0.0
-#   See the "neopixel" section for information on these parameters.
+#   See the "led" section for information on these parameters.
 ```
 
-### [PCA9533]
+### [pca9533]
 
 PCA9533 LED support. The PCA9533 is used on the mightyboard.
 
@@ -2602,34 +2599,61 @@ PCA9533 LED support. The PCA9533 is used on the mightyboard.
 #i2c_speed:
 #   See the "common I2C settings" section for a description of the
 #   above parameters.
-#initial_RED: 0
-#initial_GREEN: 0
-#initial_BLUE: 0
-#initial_WHITE: 0
-#   The PCA9533 only supports 1 or 0. The default is 0. On the
-#   mightyboard, the white led is not populated.
-#   Use GCODE to modify led values after startup.
-#   set_led led=my_pca9533 red=1 green=1 blue=1
+#initial_RED: 0.0
+#initial_GREEN: 0.0
+#initial_BLUE: 0.0
+#initial_WHITE: 0.0
+#   See the "led" section for information on these parameters.
 ```
-### [PCA9632]
+
+### [pca9632]
 
 PCA9632 LED support. The PCA9632 is used on the FlashForge Dreamer.
 
 ```
 [pca9632 my_pca9632]
 scl_pin:
-# The SCL "clock" pin. This parameter must be provided.
+#   The SCL "clock" pin. This parameter must be provided.
 sda_pin:
-# The SDA "data" pin. This parameter must be provided.
-#initial_RED: 0
-#initial_GREEN: 0
-#initial_BLUE: 0
-#initial_WHITE: 0
-# PCA9632 supports individual LED PWM.
-# Values range from 0.0 to 1.0. The default is 0.0.
-# On the FlashForge Dreamer, the white led is not populated.
-# Use GCODE to modify led values after startup.
-# set_led led=my_pca9632 red=1.0 green=1.0 blue=1.0 white=0.0
+#   The SDA "data" pin. This parameter must be provided.
+#initial_RED: 0.0
+#initial_GREEN: 0.0
+#initial_BLUE: 0.0
+#initial_WHITE: 0.0
+#   See the "led" section for information on these parameters.
+```
+
+## Additional servos, buttons, and other pins
+
+### [servo]
+
+Servos (one may define any number of sections with a "servo"
+prefix). The servos may be controlled using the SET_SERVO
+[g-code command](G-Codes.md#servo). For example: SET_SERVO
+SERVO=my_servo ANGLE=180
+
+```
+[servo my_servo]
+pin:
+#   PWM output pin controlling the servo. This parameter must be
+#   provided.
+#maximum_servo_angle: 180
+#   The maximum angle (in degrees) that this servo can be set to. The
+#   default is 180 degrees.
+#minimum_pulse_width: 0.001
+#   The minimum pulse width time (in seconds). This should correspond
+#   with an angle of 0 degrees. The default is 0.001 seconds.
+#maximum_pulse_width: 0.002
+#   The maximum pulse width time (in seconds). This should correspond
+#   with an angle of maximum_servo_angle. The default is 0.002
+#   seconds.
+#initial_angle:
+#   Initial angle (in degrees) to set the servo to. The default is to
+#   not send any signal at startup.
+#initial_pulse_width:
+#   Initial pulse width time (in seconds) to set the servo to. (This
+#   is only valid if initial_angle is not set.) The default is to not
+#   send any signal at startup.
 ```
 
 ### [gcode_button]
diff --git a/docs/G-Codes.md b/docs/G-Codes.md
index 2adcb0d9..dbfd0b85 100644
--- a/docs/G-Codes.md
+++ b/docs/G-Codes.md
@@ -690,29 +690,29 @@ scheduled to run after the stepper move completes, however if a manual
 stepper move uses SYNC=0 then future G-Code movement commands may run
 in parallel with the stepper movement.
 
-### [neopixel]
+### [led]
 
-The following command is available when a
-[neopixel config section](Config_Reference.md#neopixel) or
-[dotstar config section](Config_Reference.md#dotstar) is enabled.
+The following command is available when any of the
+[led config sections](Config_Reference.md#leds) are enabled.
 
 #### SET_LED
 `SET_LED LED=<config_name> RED=<value> GREEN=<value> BLUE=<value>
 WHITE=<value> [INDEX=<index>] [TRANSMIT=0] [SYNC=1]`: This sets the
 LED output. Each color `<value>` must be between 0.0 and 1.0. The
-WHITE option is only valid on RGBW LEDs. If multiple LED chips are
-daisy-chained then one may specify INDEX to alter the color of just
-the given chip (1 for the first chip, 2 for the second, etc.). If
-INDEX is not provided then all LEDs in the daisy-chain will be set to
-the provided color. If TRANSMIT=0 is specified then the color change
-will only be made on the next SET_LED command that does not specify
-TRANSMIT=0; this may be useful in combination with the INDEX parameter
-to batch multiple updates in a daisy-chain. By default, the SET_LED
-command will sync it's changes with other ongoing gcode commands.
-This can lead to undesirable behavior if LEDs are being set while the
-printer is not printing as it will reset the idle timeout. If careful
-timing is not needed, the optional SYNC=0 parameter can be specified
-to apply the changes instantly and not reset the idle timeout.
+WHITE option is only valid on RGBW LEDs. If the LED supports multiple
+chips in a daisy-chain then one may specify INDEX to alter the color
+of just the given chip (1 for the first chip, 2 for the second,
+etc.). If INDEX is not provided then all LEDs in the daisy-chain will
+be set to the provided color. If TRANSMIT=0 is specified then the
+color change will only be made on the next SET_LED command that does
+not specify TRANSMIT=0; this may be useful in combination with the
+INDEX parameter to batch multiple updates in a daisy-chain. By
+default, the SET_LED command will sync it's changes with other ongoing
+gcode commands.  This can lead to undesirable behavior if LEDs are
+being set while the printer is not printing as it will reset the idle
+timeout. If careful timing is not needed, the optional SYNC=0
+parameter can be specified to apply the changes without resetting the
+idle timeout.
 
 ### [output_pin]