[AVR] Algorithm Required- Home automation

[sundar-edaboard]

Hi,

We are developing home automation products switches/control plate modules, Relay modules, Dimmer modules, Curtain Control modules, RGB light Control modules, etc. are connected in the single RS485 Communication.

We have to develop GUI and firmware for the following requirement:
1. We have to scan all the devices connected in the RS485 bus using the GUI. Each device has to send the respond with the details, sothat the GUI will update what are the devices are connected. Then selecting the scanned devices configure one by one.

Guide me what are the bytes to send and receive the responding data while sent the "Scan all modules" command. Please suggest me or provide any documents to refer.

 

[Easyrider83]

Do not use 485 if you able to use CAN. It has CRC and ACK future by h/w.

 

[sundar-edaboard]

Thanks,

But the limitation of length is too less in CAN.

 

[Easyrider83]

[device index][command index][data lenght][data][crc]
Each device will respond on [search devices] command after [device index] * transmitt delay. So, each slave device will occupie their time slot.
Data received flag can be taken from MODBUS protocol - after 1.5 byte time after last byte received. One 8-bit timer will be needed.