62 lines
1.6 KiB
ReStructuredText
62 lines
1.6 KiB
ReStructuredText
.. _blink-led-sample:
|
|
|
|
PWM: Blink LED
|
|
##############
|
|
|
|
Overview
|
|
********
|
|
|
|
This is a sample app which blinks a LED using PWM.
|
|
|
|
The LED will start at a blinking frequency of 1 Hz. Every 4 seconds,
|
|
the blinking frequency will double. When the blinking frequency
|
|
reaches 64 Hz, the blinking frequency will be halved every 4 seconds
|
|
until the blinking frequency reaches 1 Hz. This completes a whole
|
|
blinking cycle. This faster-then-slower LED blinking cycle repeats forever.
|
|
|
|
Wiring
|
|
******
|
|
|
|
Nucleo_F401RE, Nucleo_L476RG, STM32F4_DISCOVERY, Nucleo_F302R8
|
|
==============================================================
|
|
Connect PWM2(PA0) to LED
|
|
|
|
Nucleo_F103RB
|
|
=============
|
|
Connect PWM1(PA8) to LED
|
|
|
|
Nucleo_L496ZG
|
|
=============
|
|
No special board setup is necessary because there are three on-board LEDs (red,
|
|
green, blue) connected to the Nucleo's PWM.
|
|
|
|
Hexiwear K64
|
|
============
|
|
No special board setup is necessary because there is an on-board RGB LED
|
|
connected to the K64 PWM.
|
|
|
|
nrf52840_pca10056
|
|
=================
|
|
No special board setup is necessary because there is an on-board LED connected.
|
|
|
|
Arduino 101
|
|
===========
|
|
You will need to connect the LED to ground and PWM0 via the shield.
|
|
You may need a current limiting resistor. See your LED datasheet.
|
|
|
|
Building and Running
|
|
********************
|
|
|
|
This sample can be built for multiple boards, in this example we will build it
|
|
for the nrf52840_pca10056 board:
|
|
|
|
.. zephyr-app-commands::
|
|
:zephyr-app: samples/basic/blink_led
|
|
:board: nrf52840_pca10056
|
|
:goals: build flash
|
|
:compact:
|
|
|
|
After flashing the image to the board, the user LED on the board should start to
|
|
blinking as discussed in overview
|
|
|