View Full Version : [Contest Entry] Summer of Projects: Project #2, RFID Door Lock

08-19-2010, 11:18 AM
Okay, so, this was my second project this summer. It's a DIY RFID Door lock system. It controls both a Dead bolt, and electric strike. Has a Keypad, and a passive IR sensor to turn on the outside lights. It also has a XBEE. It's based on a ATMEGA 328P. I used ALL the I/O on that chip. I have 1 pin that I could use for something else other that what it currently is used for (Just a jumper to change it from program to run, which isn't being used since I just hard coded the RFID tags and Keycodes) Behind the main board are two relays, one is for the outdoor lights (10 Amp relay, with a 8Amp Fuse) and other is used for the doorbell (the * key on the keypad). I've got a few videos that I will post as well.



Thanks, Connor

08-19-2010, 01:05 PM
ATMega 328 (I.E. Custom Arduino)
SparkFun Keypad
Parallax Serial RFID Reader
Parallax PIR Sensor
2 High voltage relays
1 SN754410
1 TIP120

I'm using the Parallax RFID reader (serial version). It runs at 2400 baud. I'm using interrupt based software serial, because I needed the hardware UART for the Xbee. So far, I've YET to have a miss-read using that setup. The keypad was from SparkFun. I made sure not to expose the ISP Pins to the outside. So, they're used for triggering the Strike, Deadbolt, and relays. I have a SN754410 Quad Half H-Bridge. Two channels are used for the deadbolt motor, 1 Channel for the strike, the other for the doorbell relay. I added a TIP120 darlington transistor for the relay for the exterior lights. I use 1 pin going out to the keypad to turn the LED from RED/GREEN when you swipe the tag, it also disables the RFID unit so that it doesn't queue up any additional reads. It keeps the Strike energized for 5 seconds. The strike also has a micro switch built into that gives the RFID reader a status on the standard bolt, so, when you close the door, it automatically locks the deadbolt. I also use that switch so when you turn the inside handle, it automatically unlocks the deadbolt. I switched out the doorknob for one that is always locked from the outside, but, you can always open it from the inside. This might not be too good if you have kids.. We don't so, no big deal. Next plan is to add a one-wire real time clock so that I can specify what codes/RFID tags are valid, timestamps on my logging, and set valid times for when the exterior light will turn on/off. I plan on having some circuit boards printed up, because my wife wants me to do the front door next!

Thanks, Connor

01-01-2011, 08:45 PM
Just a update on this project. It's been running in my house since this posting flawlessly, with one exception. Static Electricity.. I've shocked the doorknob once and had it reset the controller.. I think I need to ground the doorknob somehow. I added a combo DC/Battery backup supply (one used for AT&T U-verse) It has a little more juice that the standard wall wart I was using.. so the Deadbolt motor runs a tad faster now. All in all, this has been once of the funnest and most useful things I've built... and the wife LOVES it.

Other possibilities:
With the Xbee, you can network it with other units and a central computer to log all entry/exit events.. provide remote entry via internet, and provide indication of the door status. I.E. weather it's open or closed etc..

Thanks, Connor.

05-21-2012, 09:48 PM
hollywoodlocksmith.org (http://www.hollywoodlocksmith.org)

Door locks must always be quality to secure safety inside the house. Choosing the best lock is worth.