integrate an outdoor, weather resistant, wiegand pin-code and rfid reader with cloud-based, but locally redundant, pin-code and rfid validation for building access.
- rfid / pin-code reader should be cheap, tough and resistant to outdoor temperature, water and weather extremes
- system should perform a lookup against an online api to validate codes and grant door access but fall back to local lookup when internet is unavailable.
- system should periodically synchronise local access-code database with online database.
- emergency exit from secured door should always be possible, with and without electricity and/or internet.
raspberry pi (4, b, 2gb)
wiegand device io includes:
- electric lock relay output
- com
- nc (normally closed)
- no (normally open)
- alarm relay output
- aua - com
- nc (normally closed)
- no (normally open)
- power
- +12v
- gnd
- push / no
- opensw
- door 1
- bell
- bell
- alarm input
- aux in
- gnd
- wiegand reader input
- +12v
- gnd
- data 0
- data 1
- wire the wiegand device to the raspi gpio interface (via 3.3v/5v/12v adapters).
- treat the wiegand device as a dumb terminal.
- listen for and process rfid reads and pin inputs from wiegand device on the raspi.
- check reads from wiegand device against a local (raspi filesystem) database.
- grant/reject access (door unlock) based on local logic and database.
- log local reads, access and rejections locally.
- sync local database with cloud database periodically.
