On Fri, Oct 29, 2010 at 06:13:48PM +0100, Andy Pugh wrote: > On 29 October 2010 17:58, Stuart Stevenson <[email protected]> wrote: > > > ?Is there a chip or reasonable board I can use to change the sine waves to > > pulse or quadrature? > > I suspect that the Pico Resolver converter might work
I'm pretty sure these scales are optical. If it's the one I remember fiddling with, it's got light bulbs. I suspect the signals are just unconditioned light level detection. I'm not sure I know the right terminology to describe it, but they use a second piece of glass with the same pitch (?) lines in front of the master one. The second glass is at a slight angle so as you watch the light shining through it as you move the head, there is something like a moire pattern (?) that makes large areas of light and dark move perpendicular to the head's motion. It is these lines that are detected optically. For this reason I doubt there is interpolation. I bet the lines are the resolution of the device. I think they were too fine to see by naked eye. I bet very basic signal conditioning (thresholding) will be adequate to read this at full resolution. Chris ------------------------------------------------------------------------------ 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
