Do yourself a favor and do not go the cheapest route. You will burn more time and find more frustration by going cheap. If you look for and find an "exact fit", chances are you will need one more input or one more output beyond what you bought.
You will know exactly how many inputs and outputs you will need when you are done with the conversion. :-) Until then, you just "think" you know how many you need. Things I can think of you may want to add:.. An MPG, an analog output to control the spindle speed, a probe sensor input, etc. (I think that Teco supports Modbus, but you will have to tell us if it works properly or not.) Dave On 4/1/2014 11:27 PM, Gregg Eshelman wrote: > Now back to the question, now that it's established exactly what kind of > signal the scales and encoder put out. > > What *hardware* do I need to interface them safely with a PC? I've read > that it's "simple" to connect "directly" to a parallel port and a garden > variety LPT can handle two quadrature inputs. > > If I get a low profile PCI dual LPT card I'll be good to go for the > existing three axes and have a spare input for a 4th axis. > > I'm not interested in a DIY project to connect the scales. (The rest of > the refit/rebuild has been enough DIY already.) I'd like to just buy > something to plug into the LPT ports and connect the scales and encoder > to the other side - and have it usable with LCNC. Preferably without > having a ton of extra features aside from interfacing the scales and > encoder. > > Recommend something? I've searched some and findings range from "Yeah, > TTL quadrature outputs can be connected to a parallel port." (without > the author giving any specific details) to "Here's a schematic and a > BOM, now get out your soldering iron." to "Buy this expensive board that > does *anything*, of which you'll only use one function." > > The BOB I have has I/O for e-stop, spindle on/off and limit switches. > That will run off the built in LPT on the PC, or a port on the PCI card > if that will work better. (It's a better BOB than the very basic one > which came with the steppers, drives and power supplies kit.) > > Might use the spindle control relay on the BOB to run the lube pump > since the VFD has an RS232 connection. (I need to look up software for > that, and if LCNC supports whatever comm protocol TECO uses.) > > Can LCNC work with doing I/O on several LPT and COM ports at the same time? > > Or is there a single board that plugs into one parallel port, can run up > to four stepper drives, read up to four TTL quadrature scale/encoder > inputs, has an e-stop input, limit switch inputs for 3 or 4 axes, can > control spindle on/off and a lube pump *and nothing more than that*? > > In other words exactly and only what is required to operate a basic 3 or > 4 axis CNC machine tool - without a ton of added cost feature creep. > > ------------------------------------------------------------------------------ > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
