On Tue, 30 Oct 2007, Javid Butler wrote: > Date: Tue, 30 Oct 2007 19:36:35 -0600 > From: Javid Butler <[EMAIL PROTECTED]> > Reply-To: "Enhanced Machine Controller (EMC)" > <[email protected]> > To: "Enhanced Machine Controller (EMC)" <[email protected]> > Subject: Re: [Emc-users] Ethernet I/O > > Jon wrote- > >> Given all the required overhead to read and write multiple >> packets, it is already pretty close to chewing up a whole >> millisecond, and there's no way it could handle even 5 KHz >> servo update rate. So, I really don't think CAN is a good >> candidate. > > I agree. The thread started because of concern about the parport going away > on newer machines, and how to replace it. I have not seen any computers with > a CAN interface built in, which would defeat the whole purpose. We could > consider USB, but that has problems as well and met with resistance > upthread. Ethernet is relatively easy, affordable and available, and as Jon > mentioned before is isolated.
Not arguing for CAN, but Ethernet being built-in is not a great advantage unless there are 2 channels built in, since real time Ethernet (real time meaning fast enough to close a servo loop) will not get along with normal Ethernet traffic and a network connection is almost a necessity, requiring a add-in card in most cases. Not much different from the parallel port case, though faster. Peter Wallace ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
