I had an eBay "accident" last night and I have bought 3 resolver-feedback servos.
Looking at ways to drive them, I have found the Analog Devices AD2S1200 chip, which basically connects to a resolver and outputs the position and/or velocity as simulated quadrature encoder, 10-bit parallel and 3-wire serial. The ICs are not inexpensive at £24 from RS, though I have found a couple on eBay if any of the US residents fancy a fiddle. http://cgi.ebay.co.uk/AD2S1200-Resolver-to-Digital-Converter-w-Oscillator-2_W0QQitemZ390176423077 I suspect that the Pico and Mesa resolver boards use the same IC, though it is hard to be sure from the photos :-) Anyway, the point of this is to wonder what the status is of SPI communications in EMC2. That seems like the ideal way to get the data back from such a device, but all I have found on the WIki is a page set up for the development of a Hostmot2 SPI driver, and that seems not to have been updated. Is there anything in the pipeline or already available that I have missed? One use for SPI or I2C might be to drive various motor controllers with one of the inexpensive digital potentiometer chips, which seem like a very easy way to get -10V to +10V output from a digital data line. After a bit of looking at stock lists I have found something which might be easier... There are 128-step digital pots that take an up-down pulse train. I think you could drive one of them directly from a stepgen? Datasheet: http://docs-europe.origin.electrocomponents.com/webdocs/077f/0900766b8077ffdc.pdf -- atp ------------------------------------------------------------------------------ Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
