Add a README file

codelast · codelast · commit d27d145f30e5 · 2015-10-31T20:51:23.000+08:00
diff --git a/gpio/led/README.md b/gpio/led/README.md
@@ -0,0 +1,4 @@
+Demos on how to:
+* blink a LED
+* control a LED through a button(pressed or not)
+* control the brightness of a LED through PWM
