Hi all,
I'm developing some devices for my parking and home automation projects.
I'm using Advantech UbiQ as main controller. This device just has one RS-485 and a Ethernet port.
At this phase, I need to develop a protocol for my master controller.
Does any body knows a well-known RS-485 based protocol for home automation?
I have several master devices in my bus and the protocol needed to be collision detection base.
Any links or information are appreciated.
Hi,
You write "one RS-485" port but don't tell us whether it is full or half duplex and available speeds. And what programming/computation abiliities the controller has. (I am entirely unfamiliar with EbiQ.)
By "develop a protocol" I understand that you want to develop the software comand-response structure. What are your needs? Do you need handshaking? CRC ? Speed ? Presumably the remote devices need to be able to initiate communication or you wouldn't have written "collision detection base", right? Are you sure that polled-only is not adequate?
Some ASCII protocol examples that you might use or adapt in part include:
Modbus (ethernet, RS485, RS232 etc)
http://www.modbus.org/
Aprilaire/Enerzone thermostats RS-485 full duplex (I have protocol butcould find the link)
Elk Magic Module ( native RS-485 half-duplex
http://www.elkproducts.com/downloads/downloads.htm
Adicon Ocelot (native RS-485 half duplex and 232 full duplex)
http://www.appdig.com/Serprot/serprot.html
Ivie
http://www.ivie.com/pdf/anet.pdf
Centralite
http://www.centralite.com/Dealer_login/Ele...0CentraLite.pdf
JPK DMX512
http://www.jpk.co.nz/dmx512manual.html (DMX is RS-485)
Weeder Technologies
http://www.weedtech.com/an100.pdf
These are some of the HA-related protocols that I am somewhat familiar with. Most any could be used over RS-485 full duplex and polled ones over RS-485 half duplex without adding collision avoidance. There are many, many more in all manner of variations and permutations.
Of these, the only protocol that I know fer shure that you could use without copyright and trademark issues is modbus.
Tell us more about your expectations and requirements. If they are relatively simple, and also plan to homebrew the hardware, consider investigating Peter Anderon's devices, for example
http://www.phanderson.com/iom135.html. This could be adapted to RS-485 full duplex or half-duplex (the protocol appears to be polled only).
HTH .. Marc
