steeven lee
Breath LED that turn on/off or loop the brightness smoothly.
Dependents: BreathLed-demo EPD_GDE021A1_demo mbed_esp8266_demo NUCLEO_uart_flow_control
This breathing-led uses Ticker and PWM which consumes few CPU, and most important, you can use it to tell system hang.
Just init it with a PWM pin which connected to a LED.
Diff: BreathLed.h
- Revision:
- 0:13c83a6b336f
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/BreathLed.h Mon Apr 06 11:02:16 2015 +0000
@@ -0,0 +1,66 @@
+/*
+ * BreathLed.h
+ *
+ * Created on: 2015/4/6
+ * Author: steeven@gmail.com
+ */
+
+#ifndef BREATHLED_H_
+#define BREATHLED_H_
+
+#include "mbed.h"
+
+#define BREATH_STEPS 24
+
+namespace steeven {
+
+/** A breath led, used for turn on/off or loop the leds slowly with PWM.
+ */
+class BreathLed {
+
+public:
+ /**
+ * Create an BreathLed
+ *
+ * @param pin LED pin with PWM support
+ * @param time Time for the brightness transition
+ * @param hold Time for holding the brightness before next transition.
+ * Effective for loop mode.
+ */
+ BreathLed(PinName pin, float time = 1, float hold = 1);
+
+ virtual ~BreathLed();
+
+ /* Group: Access Methods */
+
+ /**
+ * start loop the led
+ */
+ void loop(float time = 1, float hold = 1);
+
+ /**
+ * turn on the led
+ */
+ void on();
+
+ /**
+ * turn off the led
+ */
+ void off();
+
+
+protected:
+ PwmOut _pin;
+ int _mode; //loop, on, off
+ float _time; //time of brightness transition
+ float _hold; //time to hold in loop
+ Ticker _ticker;
+
+ int _off; //current direction
+ int _step; //current brightness
+
+ void step_tick();
+ void hold_tick();
+};
+}
+#endif /* BREATHLED_H_ */