1.1 DALI Terminology

The list below contains basic DALI terminology used in the protocol:

• Control Device: A device that transmits commands to other devices connected to the same bus. A control device can also receive commands and backward frames.
• Control Gear: A device that receives commands in order to control its output.
• Ballast: An electronic device that regulates current and voltage to the lamp.
• Frame: A packet of information consisting of a Start bit, command/data byte(s), and a Stop condition.
• Forward Frame: The frame sent by the control device to the control gear. A forward frame consists of a Start bit, an address byte, up to two data bytes, and a Stop condition.
• Backward Frame: The frame sent back to the control device from a responding control gear. The backward frame consists of a Start bit, one data byte, and a Stop condition.
• Command: A specific instruction intended to cause a reaction in a receiver.
• Short Address: The address of an individual control gear within the system.
• Group Address: The address of a group of control gears within the system.
• Broadcast: The address used to communicate with all control gears within the system.
• Arc Power: Power supplied to the lighting source.
• Direct Arc Power Control (DAPC): A method that immediately sets an individual or multiple control gears to a specific power level.
• Scene: A configurable preset lighting level.
• Building Management System (BMS): A computer-based control system installed in buildings that controls and monitors the mechanical and electrical equipment of a building.