Add readme.

1 files changed, 23 insertions, 3 deletions

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-The carrier frequency of the radio module is 433MHz.
+SMART HOME
+
+This is a collection of projects I'm currently working on to make our home
+smarter. The project is in its early stages. This project considers efficiency
+and environmental friendliness as part of the problem constraints. That means
+'working' solutions aren't enough. They must be efficient.
+
+THE DOOR LOCK
+
+The door lock project aims to drive my door lock using a fingerprint sensor
+module (FPM). In its current version, the front of the door has FPM connected
+to an ATmega328P microcontroller. The back of the door has a servo connected to
+another ATmega328P. Both modules have 2.4GHz NRF24L01+ RFMs connected to them.
+
+When the FPM authenticates a user, the MCU establishes a secure connection with
+the back of the door, exchanges a session key, and transmits a lock/unlock 
+command to the servo. The wireless protocol allowed me to get it working with
+modifying our old Japanese door lock. I wrote all the firmware and drivers of
+this project from scratch.
+
+Although I designed this around RFM to learn more about RFM, the architecture
+can be made more power-efficient if I toss the RFMs. I'm in the midst of making
+these changes to the system.
 
-Arduino Uno without sleep: 28.5 mA draw
-Arduino Uno power down: 18.4 mA draw