XML over real time Ethernet.

Graham Stabler

Perhaps a stupid question but can the propeller do this? I know the propeller has no problem with real time and can do Ethernet with a module of some sort but I'm not sure if real time Ethernet differs in other ways.

The propeller would be sending commands coded in XML mainly.

Graham

Kevin Wood

XML is basically just text... but there's usually a lot of it. If you can figure out a way to efficiently get it into the packets, you should be able to do it.

Heater.

Good old normal Ethernet as we know it is not real-time. That is it has a non-deterministic timing on the delivery of packets. I presume most Ethernet modules you might find for Ethernet with an MCU like the Prop are not real-time.

However if you can avoid collisions on your Ethernet connection I guess it becomes about as real-time as you may ever need. To avoid collisions just be sure there is only two nodes on the ethernet segment, say a single cable directly from Prop to PC Ethernet card.

prof_braino

Graham Stabler wrote: »

if real time Ethernet differs in other ways.

This thread talked about a realtime scheme using ethernet, they called it etherCAT, is this what you are after?

http://forums.parallax.com/showthread.php?131382-Realtime-Propeller-Network-over-Ethernet-or-quot-the-propeller-between-propellers-quot&highlight=ethernet+realtime

Graham Stabler

It seems there are several implementations one of which is etherCAT:

http://www.ccontrols.com/pdf/volume5n4.pdf