Building Badges The Hard Way
What’s a hacker to do to profess his love for his dearest beloved? [Nitesh Kadyan] built his lady-love this awesome LED pendant – the LED BLE Hearty Necklace Badge.
The hardware is pretty vanilla by today’s hacker standards. An ATMega328p does most of the heavy lifting. An HM-11 BLE module provides connection to an Android mobile app. Two 74HC595 shift registers drive 16 columns of red LEDs and a ULN2803 sinks current from the 8 rows. The power section consists of a charger for the 320mAh LiPo and an LDO for the BLE module. All the parts are SMD with …read more