John Kasunich wrote: >The Pico systems boards (USC and UPC) have opto-22 modules on most of >their I/O, which isn't good for encoder signals. > In fact, they do work. You should be able to go to at least 100,000 counts a second through the optocoupler - so it is definitely not the limiting factor. Of course, the computer's servo loop will not be reading the digital inputs anywhere near that fast. Normally, the digital inputs are only sampled at the servo update rate (this is a driver design limitation) so an encoder shouldn't count over, say, 500 counts a second to avoid missed pulses. With a 40 count/rev encoder, that would still allow you to handle 10 RPS.
One thing is that the digital inputs are ISOLATED, so you have to have a common ground between the encoder and the digital input ground. Jon ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
