From: Jon E. <el...@pi...> - 2008-03-30 03:23:34
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Neil Whelchel wrote: > Hello, > I have joined this list because I an working on a project to convert my > old CNC mill and manual lathe to EMC and I saw that there are what seem to > be limited methods of interfacing EMC to the outside world, and I think I > might be able to help in this area, among others. Sure there is the > parallel port, and a hand full of (supported) ISA and PIC boards, but none > of them seem to provide an optimal interface, and others are simply not in > the right price range to make a project feasible. I have been tossing > around the idea for a few months now of creating some very cheap (open > source) microcontroller based I/O modules that communicate using Ethernet > at the layer 3 level (Network Layer). There is a real-time Ethernet driver already in existance, but there are a number of restrictions on how it works. Also, these restrictions means it won't work with off the shelf ethernet micros and their off the shelf ethernet stacks, such as Atmel and NXP make. At least, that was my understanding. Whether the micro's library can be adjusted to make it work with the RT-net, I don't know. The RT-net requires total isolation of the RT part from the WAN with a router that can handle the RT-net flavor, so that pretty much has to be another computer with two ethernet cards/ports. I wanted to provide an ethernet interface to my boards, which are parallel port based right now. But, this was just over my head and beyond the time I had available. Jon |