> Jeff Epler wrote: >> USB-attached motion control interfaces are not a good match for emc2. >> >> > I have not intention to use an usb motion control controlled by a RT > HAL-driver of EMC. > The "external driver " (connected with USB) has an internal motion > controler (with its PID) and its input ( PC--->Driver ) is similar to > stepper motor. Obviously, the data input is buffered (into "external > driver") to allow the "external driver" to observe the trajectory, and > allows the USB sending data in not realtime. The average throughput of > the USB allows that. > The "interface" from EMC to "external driver" for me would be to have > EMC generate the positions and axis directions and provide them to a > "external driver" . > Do you think it is possible to realize this type of interface?
Possible, maybe. Easy, certainly not. You would probably need to split emc2 (and all the dataflows) in half. Probably somewhere in the emctask/emccanon level. Basicly you have task which calls the interpreter to read the g-code and convert to canonical commands. Those get sent to the emc2 motion controller now, and should be converted to your format and sent to your usb device. The general idea is not that complicated, but as usual the problem lies in the details. How often do you want to communicate with the USB hardware? Do you plan to support feedrate override? If you do, how should the user interface send that to the USB device? And what happens to the current, active, motions? How often do you read feedback from the USB device? These are all questions that should be answered by a proper protocol/function design. Attempting to code something before you have a valid design, will more than definately fail. Regards, Alex ------------------------------------------------------------------------------ Create and Deploy Rich Internet Apps outside the browser with Adobe(R)AIR(TM) software. With Adobe AIR, Ajax developers can use existing skills and code to build responsive, highly engaging applications that combine the power of local resources and data with the reach of the web. Download the Adobe AIR SDK and Ajax docs to start building applications today-http://p.sf.net/sfu/adobe-com _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
