HomeGenie Forum

Automation Program Plugins and Wizard Scripting => Raspberry Pi GPIO/SPI/I2C => Topic started by: anton2122 on May 14, 2014, 08:59:28 PM

Title: RS485 support for Raspberry
Post by: anton2122 on May 14, 2014, 08:59:28 PM

I have an idea about new communication protocol. In some project it better using devices whith RS485 connection (low cost, long distances). I have a scheme for communicating Raspberry whith Home Genie to RS485 net. It need chip MAX485 and some code. Pin 23 is needing for control direction data transfer. High level is transmission data, Low level is recieving data. So all communication is simple serial connection. I am not programmer, so i cannot modifying module "serial connection" for controlling gpio and convert data to simple rs485 protocol. Who are interested, glade to help theory.

Title: Re: RS485 support for Raspberry
Post by: beppe2810 on May 28, 2014, 07:20:14 PM

I solved a similar problem with this accessory

http://www.ebay.com/itm/170914684278?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649 (http://www.ebay.com/itm/170914684278?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649)

Title: Re: RS485 support for Raspberry
Post by: anton2122 on June 10, 2014, 09:38:51 PM

Yes it is good idea, but what protocol you have using?

Title: Re: RS485 support for Raspberry
Post by: mmoiron on November 18, 2014, 12:03:46 AM

Hi. Every one.
This is my first step into home automation, although industrial automation has been keeping me busy for the last 15 yrs :-)
I've been playing around with Arduino, RS485 and Modbus. Modbus is an "openly published and royalty-free communication protocol" (http://en.wikipedia.org/wiki/Modbus (http://en.wikipedia.org/wiki/Modbus)), and there are several examples (and libraries) available for Arduino. It alows read / write of both analog and digital registers.
Additionally, there is an  open source project, SCADABR (http://www.scadabr.org.br/ (http://www.scadabr.org.br/)) of a SCADA system (http://en.wikipedia.org/wiki/SCADA (http://en.wikipedia.org/wiki/SCADA)) that has the Modbus connectivity implemented (in java, I think) from were we might (?) get some code from. The website's in portuguese but I can help you with that.
It'd be great to have open source software, like HG, linked with open source hardware, like Arduino in a Home Automation network.
Best regards,
M