Top 5 honeywell open source projects

Understanding the RF signal used in the Honeywell RCWL300A, RCWL330A, Series 3, 5, 9 and Decor Series Wireless Chimes

RAMSES-II is a Honeywell RF protocol for HVAC and CH/DHW

The Homebridge Honeywell Home plugin allows you to access your Honeywell Home thermostat from HomeKit.

ECP keypad implementation for Arduino/AVR

Locates Honeywell/Tridium/Niagara HVAC JACEs/Controllers via HTTP fingerprints/strings. Very handy for vulnerability/pentesting.