2017-04-05 03:20:40 +08:00
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.. _rgb-led-sample:
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2017-01-09 22:12:15 +08:00
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PWM: RGB LED
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############
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Overview
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2017-01-21 07:58:05 +08:00
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********
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2017-01-09 22:12:15 +08:00
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2016-10-19 06:35:20 +08:00
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This is a sample app which drives a RGB LED using PWM.
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There are three LEDs of single color in a RGB LED. The
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three LEDs will be driven by a pwm port each. The pulse
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width for each pwm port will change from zero to period.
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So, the brightness for each LED will change from dark to
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max brightness in 11 steps. The three "for" loops (one
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for each LED) will generate 1331 combinations and so,
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1331 different colors. The whole process will repeat for
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ever.
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2017-01-09 22:12:15 +08:00
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Wiring
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2017-01-21 07:58:05 +08:00
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******
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2017-01-09 22:12:15 +08:00
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2016-10-19 06:35:20 +08:00
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Arduino 101
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2017-01-21 07:58:05 +08:00
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===========
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2017-01-09 22:12:15 +08:00
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2016-10-19 06:35:20 +08:00
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You will need to connect the LED pins to PWM0, PWM1 and PWM2
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2017-06-13 05:30:03 +08:00
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on Arduino 101 via the shield. Depending on what kind of RGB
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2016-10-19 06:35:20 +08:00
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LED you are using, please connect the common cathode to the
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ground or the common anode to Vcc. You need current limiting
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resistor for each of the single color LEDs.
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The sample app requires three PWM ports. So, it can not work
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on Quark D2000 platform.
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2017-01-09 22:12:15 +08:00
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2017-07-28 03:37:25 +08:00
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Hexiwear K64
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============
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No special board setup is necessary because there is an on-board RGB LED
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connected to the K64 PWM.
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2017-01-09 22:12:15 +08:00
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Building and Running
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2017-01-21 07:58:05 +08:00
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********************
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2017-01-09 22:12:15 +08:00
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This samples does not output anything to the console. It can be built and
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flashed to a board as follows:
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.. code-block:: console
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$ cd samples/basic/rgb_led
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$ make BOARD=arduino_101
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$ make BOARD=arduino_101 flash
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