On Sun, 2010-10-31 at 17:50 +1100, Erik Christiansen wrote: > On Sat, Oct 30, 2010 at 10:54:37PM -0700, Kirk Wallace wrote: ... snip > > lots of people are using it successfully. I think one needs either a > > higher frequency or use PDM instead. ... snip > If your PDM is "Pulse Duration Modulation", then that's fine, but > wikipedia's "Pulse Density Modulation", isn't what's needed, at all. > > Erik
According to the documentation: http://www.linuxcnc.org/docview/html//man/man9/pwmgen.9.html it's pulse density, but I would think the duty cycle would be a constant 50%, which wouldn't work. I haven't tried it, but I have seen it mentioned on this list a few times. It may have to do with how the filter is set up. Maybe like a charge pump, you get more pumps per unit of time as the pulse density goes up. I looked at the EPP material some more and there is a connector pin for transferring data and one for address. In order to just get something working on a very basic level, I can forgo the EPP standard and use EMC2's parport driver: http://www.linuxcnc.org/docview/html//hal_drivers.html to bit bang my own protocol. Maybe a simple 8 bits of data out and a strobe. -- Kirk Wallace http://www.wallacecompany.com/machine_shop/ http://www.wallacecompany.com/E45/index.html California, USA ------------------------------------------------------------------------------ Nokia and AT&T present the 2010 Calling All Innovators-North America contest Create new apps & games for the Nokia N8 for consumers in U.S. and Canada $10 million total in prizes - $4M cash, 500 devices, nearly $6M in marketing Develop with Nokia Qt SDK, Web Runtime, or Java and Publish to Ovi Store http://p.sf.net/sfu/nokia-dev2dev _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
