On Wed, 31 Oct 2007, Jon Elson wrote: > Date: Wed, 31 Oct 2007 00:48:31 -0600 > From: Jon Elson <[EMAIL PROTECTED]> > Reply-To: "Enhanced Machine Controller (EMC)" > <[email protected]> > To: "Enhanced Machine Controller (EMC)" <[email protected]> > Subject: Re: [Emc-users] Ethernet I/O > > Peter C. Wallace wrote: >>> $300, using pluggable terminal strips ;) >> >> >> >> Heh, We told Digikey the Avnet price and they came down to ~10.00... >> >> For a parallel port replacement Ethernet, maybe a thing to consider is just a >> single point to point link to the (multi axis) endpoint and some very simple >> master slave protocol. The slave would get a packet, unpack to hardware >> registers, and echo a new packet or return data. > Yes, but it has to have a real time driver module, that's the > problem. And, it would require two ethernet ports on the > system, if you wanted to also be on the local network.
But for point to point, all you do is setup the packet in memory, setup the DMA controller and tweak the Enet chip >> >> I've been thinking of doing this with a low cost FPGA card like the 7I43. >> Just >> replace the USB interface with a LM3S8933 or something (Nice because it has a >> built in PHY and IEEE 1588 (no speed demon though)) > For what I want to do with t, it has to be pretty fast. I'd > want to leave the possibility it could run at a 10 KHz servo > update rate, otherwise it is a step BACK from the parallel port. > > Jon > I think thats quite doable with a simple point to point protocol, If protocol bloat creeps in then you would need more horsepower. 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
