Emergency strobe light, AVR project
Channel: Thomas J.
Date: 2015-02-25

The emergency strobe light consists of 33 high intensive 5 mm LEDs and control circuit. It has four sequences, and can be set on a single sequence or to cycle through every fifth second. When selecting a sequence manually it is stored in EEPROM and continues on power-up. If an external controlling unit is plugged in; the internal sequences will stop and the external unit is in control. This makes it possible to synchronize multiple units. LEDs are driven by a PWM output, module is powered by 9-24V. 

More information here: https://blog.cavelab.dev/2007/10/avr-blue-led-strobe/