Thought I'd maybe ask a question that I think is relevant to this discussion.
First some background. I've been using both licensed Light-O-Rama and the free VIXEN light show software. Back when I bought Light-O-Rama Vixen wasn't really available yet. Now it's pretty cool. For those of you who don't light up their house at Christmas with lights that blink in time to music VIXEN is a software program that can send UDP messages over Ethernet to a controller that then pulls out 513 bytes and sends them out over an RS485 link. The timing of the break character at the beginning of the string of bytes signals the devices out there that this is a new packet. The first byte is the universe number and so multiple universes can co-exist. Bit rate is exactly 250kbps. Not a normal baud rate. And the timing can be a bit critical. Each byte or combination of bytes can consist of commands or data like a pan/tilt with a flood lamp. The message data may contain position and lamp colour/intensity. Anyway, the software running on the PC broadcasts UDP. I could just a easily be TCP/IP with guaranteed deliver and packet order. The point is times have changed and the need to use some sort of HTML based scripting language isn't really as much as a requirement anymore. The idea of write once, compiler anywhere with Lazarus Pascal (similar to Delphi 5) that allows the software user interface and trajectory planner to run on one machine and the actual motion control on an embedded system with an RTOS. Or alternatively if a commercial system was desired Embarcadero's RAD Studio with both C++ and Delphi can create amazing graphics centric programs and easily and dynamically along with any needed networking and database support. Not only that they can target PCs, Apples, Linux, Android and the various kinds of tablets just by selecting the target. And not only the target system but with that target's look and feel. So a simple CAD program that can do the CAM part and then control a machine linked via Ethernet is entirely within the capabilities of what is now available in hardware. The special driver interface to something like a MESA 7i92H which connects via Ethernet could run off this system. In fact I'm not sure why the PC that I have beside the machine couldn't be located in another room other than not having physical control over it. Ie. The loop between buttons attached to the 7i92H needs to be closed as in the PC program must be running to jog an axis. So we're back to my original suggestion that a simple machine controller which can react to buttons and an MPG for local control but no trajectory planning perhaps has an Ethernet connection, not to an HTML application but a dedicated application created with a write once compile or run anywhere application. And a surplus tablet with touch screen that can sit by the machine for more sophisticated local control but can be set off line to allow that PC somewhere else to run the system lights out. I'm going to suggest that the UDP or TCP/IP protocol is the heart of this sort of system. Define it correctly to deal with the real time trajectories and control and that small embedded system can be tucked into the control cabinet while the real system can be anywhere. John Dammeyer _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
