I’m looking for a reliable low-cost multi-master automation system to be adopted by the opnode project as standard wired fieldbus.
Opnode project: opnode.org
At this moment opn-one is performing very well but 1-Wire is a too weak technology for being used in control applications with lots of endpoints. CAN, instead, was specially conceived to be used in harsh environments: it’s robust, fast, multi-master, provides great noise immunity, etc.
Under these requirements and being opnode an open source project, I first took a glance at some of the CAN open protocols: Canopen, DeviceNet, vscp, etc. None of them convinced me due to some of these reasons: the community already owns some opnode-style device, too complicated protocol, lack of commercial nodes, expensive controllers, etc.
Now I’m more looking for a commercial system where an opnode gateway (xAPtoCAN?) could fit. What would this opnode be supposed to do?
- Web interface for configuring, monitoring and controlling devices
- xAP BSC interface (see xapautomation.org) -> integration with other xAP devices in the same LAN
- Web programmable Event Manager
This new device should provide these benefits to the fieldbus technology (CAN in this case):
- Possibility to integrate several independent CAN networks via xAP (UDP/IP)
- Integration with third-party technologies (1-Wire, X10, CBus, etc)
- Provide more intelligence to the CAN network through the Event Manager
- Integration with superior controllers as HomeSeer, HAL or opn-max (another opnode project)
- Monitor and control any device/endpoint via Web
For this design and bearing in mind that Velleman already provides a RS232 interface, the easiest solution would be the use of opn-232. With the appropriate customization, opn-232 (uClinux platform) should be an excellent platform for this project.
I have the following questions though:
- What bitrate does the Velbus CAN system use?
- Are you planning to develop any kind of AD converter? A generic AD converter would be the perfect complement for the current family of products IMO
- Does Velleman provide the CAN protocol… or only the protocol used by the RS232 interface? I’m just thinking in the possibility of developing custom nodes compatible with the Velbus system (a LCD user interface, 1-Wire gateway, etc)
I forgot to say that I’m a happy consumer of Velleman’s products and really appreciate your current work on the home automation area.