Azure Access Technology BLU-IO21
Downstream I/O Board

The BLU-IO21 is a single-door IO board that, while offering general purpose IO, can most effectively be paired with multi-dropped OSDP readers for managing more doors from a single controller. The IO21 can share the same RS485 and power wiring as the OSDP readers. A custom, labeled enclosure allows for installation at the “edge”; close to the door.


  • Fully encrypted serial communications
  • OSDP protocol (plus enhancements) to communicate to the IC
  • 2 Supervised or Unsupervised Inputs
  • 1 Relay Output
  • Status LEDs
  • Configuration pushbuttons
  • Offline Mode allowing for basic access control functionality when not communicating with the IC
  • Custom, labeled enclosure with mounting flanges and tamper sensor


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