Hello, I am working at connecting a 7i84 IO card to a machine that I am refitting a newer Linuxcnc PC to. The old PC used an ISA card for IO. That will no longer be an option with a newer PC.
My questions, the servo drives used 5v TTL signals for IO signals specifically the ready/fault output, and the enable input. How should I interface these with the new 7i84 card (which is using 24v field power)? The ready/fault output seems simple enough. It is an "open collector outputs without pull-up resistors, they are rated for switching non-inductive loads up to 40V at a maximum of 100mA" (quote from the drive's manual). So I simply need to add a 24v pullup for each of those signals. The question is what size pullup resistor should I use? The harder question for me is how to handle the 5v drive enables? Would it be best just to connect them to via a relay? Or would there be a better way? Other Mesa cards in this system, a 5i25, 7i85S, and 7i88. Both parallel port headers are used on the 5i25. The smart serial port on the 7i85s is used to connect the 7i84. All of the step/dir outputs on the 7i88 are being used. The only IO not being used are on the 7i84, one encoder input and one step/dir output pair on the 7i85s. Would it be ok to try to use one of the free the step or dir outputs as the 5v enable signal for all 3 servo drives or is a relay on one of the 7i84 outputs a better idea? Todd Zuercher P. Graham Dunn Inc.<http://www.pgrahamdunn.com/index.php> 630 Henry Street Dalton, Ohio 44618 Phone: (330)828-2105ext. 2031 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
