The Microchip DALI2.0 Slave solution is based on the 8-bit MCU of the tinyAVR series. The solution conforms to the DALI2.0 protocol standards IEC62386-102 (Control Gear) and IEC62386-207 (LED Modules) released by the DiiA Alliance 2014.

Implementation principle

The DALI2.0 Slave control board receives commands from the master station on the DALI bus, completes the encoding and decoding of the DALI2.0 protocol through the on-board MCU, and realizes the master station's control of the Slave end, turning on LED, turning off LED, PWM to dimming LED etc . This solution has passed the DALI2.0 protocol standard. All the hardware and software are completely open source, which brings great convenience to the projects that need to be designed for DALI2.0. The reference of DALI2.0 Slave demo board is as follows.

Program features 

  • Compatible with DALI1.0

  • Complies with IEC62386-101, IEC62386-102, IEC62386-207 (DT6) standards

  • DALI2.0 software protocol stack <8KB

  • Support 0-100% full range PWM dimming

  • Provide programming and debugging UPDI interface

  • MCU core independent peripheral (CIP)

  • In addition to DALI protocol, 16KB Flash is convenient for users to add custom functions

  • USB 5VDC power supply MCU, DALI bus 16VDC

  • Wide temperature range -40 ° C to + 105 ° C

Solution advantages 

  • Open source reference design, software source code, Gerber, PCB, schematic, etc.

  • Complies with IEC62386 standard, can be compatible with any equipment that conforms to DALI protocol

  • Compatible with DALI1.0, can be easily ported to DALI2.0

  • Atmel Studio / START development tools are simple and easy to use, shortening customer product development time

  • Passed CE / FCC certification

DALI interface circuit 

The DALI interface is used for communication between the DALI bus and the MCU. The DALI bus is a pair of differential signals. In order to avoid the risk of common ground, the voltage signal of the DALI bus and the MCU is isolated by an optocoupler. Coupled components, DALI2.0 and DALI1.0 hardware interface is exactly the same.

Solution hardware block diagram

The DALI interface receives commands on the bus, and the MCU software encodes and decodes the commands to achieve PWM output to dim the LED. The comparator uses Microchip's MIC833, USB is used to power the Slave board, LEDs are power status indicators, and UPDI is debugging. Burn interface.

Software Architecture 

The program uses Atmel tinyAVR 1 series MCU ATtiny1617, uses MCU external interrupt and internal timer and E2PROM, the chip Flash 16KB, which DALI2.0 protocol takes about 8KB, the remaining 8KB Flash is used for application programming. The driver initialization part of the MCU can be configured through Atmel Start, and the DALI protocol is called through the API function. The customer only needs to focus on the preparation of the application. The public software source code can be downloaded from the Atmel Start website.

DALI system established 

A DALI system needs DALI Master, DALI Power, and DALI Slave. DALI Power is to supply power to the DALI bus. A system has one DALI Master, and up to 64 DALI Slaves can be connected.

The DALI Master terminal is based on Atmel's ATxmega32E5. The on-board UART to USB can be connected to a PC. The external 16V power supply provides power to the DALI bus. After the DALI Master and DALI Slave are successfully connected to the DALI bus, the PC software at the Master terminal can be scanned. To all the Slave devices, control the Slave LED lights through the PC software. 

PC control software

DALI Tools are as follows, you can send commands in the form of broadcast, you can also specify the group address to send commands, through the PC software commands to control the Slave LED on, off, brightness adjustment.

The source code of the above Master and Slave can be downloaded from the official website of Microchip or Atmel Start. The configuration information of DEMO can also be seen on Start. After the compilation is successful, it can be downloaded to the MCU through UPDI.

Application field

  • Suitable for all kinds of commercial and architectural lighting