HACCSY – Hackerspace Access Control and Check in System

HACCSY – Hackerspace Access Control and Check in System

HACCSY abbreviation stands for Hackerspace Access Control and Check in System and that’s pretty much what it does.

HACCSY app is meant to run on a RaspberryPi that’s connected to internet and the front door electric strike lock. It does the job of a simple Check in System and Door Access Control System (2 in 1), it queries a REST service by handing it the scanned in RFID card reader and it will return ‘true’ if the key owner owes less than 2 months worth of their monthly payment. It will return ‘false’ otherwise. It does the same for checking in and out. The computer would then send the signal to the door lock actuator to open it if returned true or do nothing if false. It has a check IN/OUT button to indicate Check IN or Check OUT. It also has an LCD backlight display that displays messages for the user, and an RGB LED that turns RED for Access Denied, GREEN for Access Granted and WHITE to indicate offline mode. Through the REST API, you can also make it available for others to see if the hackerspace is open or not. See working example¬†on the website header at

Code available on Github

HACCSY is built with the following hardware and electronic components:

  • * Raspberry Pi
  • * USB RFID reader (hidraw0)
  • * AdaFruit LCD screen,
  • * 12V Power supply (12V LED power supply)
  • * 2 push buttons (Check in/out button, Exit button)
  • * Electric strike lock.
  • * N-Channel Mosfet (FK106269)
  • * Mosfet Resistor 1/4W ~47 kOhm
  • * Display Resistor 1/4W 470 Ohm
  • * Display Pot 10 kOhm
  • * 3x LED resistors ~330 Ohm
  • * Protection Diode 1N4007
  • * Snubber Resistor 100 Ohm
  • * Snubber Capacitor 0.47 uF 100V (not electrolythic)



HACCSY’s code is based on ACON

This code is broken into two parts to make HACCSY work with Seltzer.

Code Author: Altin Ukshini – altin.uskhini[AT]gmail[DOT]com
Hardware and wiring: Dijon Vula – dijonvula[AT]gmail[DOT]com

Wiring schema

Credits: Dijon Vula – dijonvula[AT]gmail[DOT]com

Note: We will update the schema soon, until then, please use a Snubber or an reverse-biased diode at the electric strike lock to eliminate any noise / inductive kick in the circuit – this usually affects the LCD screen and will make it display scrambled characters.


The python files stored in the RaspberryPi folder go in the /home/pi folder. The Seltzer PHP files need to be uploaded via FTP to the same web server where you’ve installed Seltzer. It should line up where this “api” folder is under the “crm” folder so that the URL looks like “…..

If you don’t want it to interface with Seltzer you could take out the part that updates the whitelist file and just populate the file manually with the valid users and their RFID serial numbers. The whitelist file should have a JSON array like this:

[{"firstName":"Josh","lastName":"Pritt","serial":"8045AB453449"},{"firstName":"Tony","lastName":"Bellomo","serial":"6554557774BC"},{"firstName":"Arlo","lastName":"Del Rosario","serial":"4944D8938D11"}]

Then make sure to create the new tables and new columns by importing the update.sql file via phpmyadmin to your seltzer database.

See the documentation here for more detailed steps:

There are several variables to set. They are all at the top and usually are ALL CAPS. Change these values if you need to such as the USERNAME and PASSWORD for your email server or HTTPAuth authenticating with htaccess when using REST API.

You need to run a few commands on the Raspberry Pi command line (terminal) to get it to run the Python scripts correctly.

sudo apt-get install python-dev python-rpi.gpio

Then get the AdaFruit LCD screen library and setup the I2C pins on the GPIO by following these directions:×2-character-lcd-plus-keypad-for-raspberry-pi/usage

NOTE: In our case, we have used different pins, so when testing the libraries, make sure to use our pin setup!

Finally, set up the RPi so that it runs the main python script as soon as it boots up as root user:

sudo su
crontab -e

add this to the end of the cron:

@reboot python /home/pi/ & python /home/pi/ & python /home/pi/ &
@reboot bash /home/pi/

then save and exit and reboot the pi.

If you’re using a Wifi USB adapter, edit /etc/network/interfaces/ and at the wlan0 configuration add allow-hotplug wlan0 #and wireless-power off

Your configuration should look somewhat like this:

auto lo iface 
lo inet loopback

iface etho0 dhcp
auto eth0
allow-hotplug eth0
iface eth0 inet manual

auto wlan0
allow-hotplug wlan0
iface wlan0 inet dhcp
wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf
wireless-power off

Here’s another tweak for the power management configuration
Create a new file:

sudo nano /etc/modprobe.d/8192cu.conf


options 8192cu rtw_power_mgnt=0 rtw_enusbss=0

then save and exit and reboot the pi.

The following should output 0 after reboot

cat /sys/module/8192cu/parameters/rtw_power_mgnt