door

GPIO door lock control

• Tested on a Pi Zero W running Raspbian GNU/Linux 9
• The Pi should be powered with an adapter rated between 5.1V - 5.2V, 2.5A
• The card readers tested are of the type PN532
• The door lock is triggered by raising a single GPIO pin
• Pins are numbered using the wiringPi scheme
• The cardreader is assumed connected with I²C on interface #1 (the lowest I²C pin numbers)
• Authorized card numbers are downloaded from hackerhula

Wiring

Schematics of the circuit can be found in /schematics which have been created with gschem.

Installation

Install dependencies

# apt install wiringpi libnfc5 libnfc-dev build-essential

Build nfcreader

$ cd nfcreader
$ make

Enable I²C interface

# echo 'dtparam=i2c_arm=on' >> /boot/config.txt

Specify where the NFC device can be found by libnfc

# echo 'device.connstring = "pn532_i2c:/dev/i2c-1"' > /etc/nfc/libnfc.conf

Copy systemd service file to system folder

# cp doord.service /etc/systemd/system

Set password to upstream card list in environment variable

# vim /etc/systemd/system/doord.service

Reload, enable and start the service

# systemctl daemon-reload && systemctl enable doord.service && systemctl start doord.service

Reboot!

Usage

Trigger door lock

$ GPIO_PIN_DOOR=0 STAY_UNLOCKED_SEC=2 open-door

Trigger lock over network

SSH

Connect with SSH from the local network and use the password stored from hackerpass infrastructure/hackeriet-door-trigger. The shell of the entry user is the open-door script. Connect with caution.

$ ssh entry@10.0.20.10

Web interface

NOTE Up to date information about this functionality can be found in https://github.com/hackeriet/door-remote

https://door-remote.hackeriet.no

Developing

See /test/run-test.sh to see how to use mocks in doord.py. The test script currently has to be run from the project root to get correct paths.

Debugging and Troubleshooting

Things to check

• Make sure wiring is correct. Easy to mix up CLOCK and DATA wires when connecting the I²C device.
• Measure output voltage on the 5V rail. If it's below 5 volts, the card readers may malfunction.
• Make sure the power rating of the power supply is as high as expected (see first section of this document)

Helpful binaries

• To debug the I²C interface, i2c-tools contains some nice utils. Specifically i2cdetect which dumps all addresses found on the I²C bus (i2cdetect -y 1 for bus number 1)
• libnfc-bin and libnfc-examples contains some libnfc utilities. Specifically nfc-poll and nfc-scan-devices are helpful in detecting a correctly connected nfc device

Verify daemon is running as it should

# journalctl -u doord.service -f

Thanks to

• jonnor, Mathsterk @trygvis from #bitraf @ chat.freenode.org for wiring advice

References

• wiringPi wiring scheme
• The gpio utility
• Bash exit traps
• Power a 5V relay from GPIO pins
• Logging in Systemd