Multi-Credential Access Control
Door & perimeter controller
A feature-complete access-control platform on Atmel SAMD21 — man-trap, controlled access, maintenance mode and tamper detection with the full spread of industry credential technologies — in production, with performance work that cut reaction time 2× and OTA time 5×.
- Client
- A US security-hardware client (name withheld — NDA)
- Delivery
- Delivered by our founder at IoTech Designs
- Role
- Research & Solution Architect — architecture, core libraries, foundational firmware
- Timeline
- 2019 – 2021
Stack
help The problem
Access control is not one feature but a family of them, and they have to interlock reliably because the failure mode is a security breach. A single controller had to support multiple credential technologies so it drops into existing installations, enforce access logic like man-trap interlocks and maintenance mode, detect tampering, support safe field updates, and network with other controllers over an industrial bus — all on a modest microcontroller.
build What we built
- The access-control feature set: man-trap interlocked door pairs, controlled access, maintenance mode, tamper detection and related logic.
- Multi-credential support across RFID, 1-Wire, Wiegand, HID and OSDP — the modern supervised, encrypted access-control protocol — so the controller speaks to virtually any reader in the field.
- Rich I/O: 16 supervised resistive inputs plus 4 wet and 4 dry contacts, enough to wire real doors, sensors and relays without external expanders, with an SPI-driven graphical UI on the device.
- OTA firmware updates and RS485 networking for multi-controller installations.
- Hard real-time performance work — a reactive event module dispatching events the moment they occur cut reaction time 2×, an event-packing algorithm lowered bus bandwidth, and a bootloader rework cut OTA time 5×.
check_circle The result
- done A production-grade access-control platform covering the core commercial feature set on a single controller, in production with a US security-hardware client.
- done Security-critical embedded systems, deep access-control domain knowledge, industrial I/O and networking, and architecture built for reuse across a product line.