Hi Saleem,
Firstly - unless there are reasons you haven't yet explained I would use the platform flash parts for configuration, not the XC18V04. The XC2V2000 requires 7.5Mbits of config memory so you would be able to use a single
8Mbit part with no problems at all. The platform flash parts are cheaper and available in much larger sizes (see here:
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Regarding the ZBT RAMS - please take a look at the following apps note:
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Although it was written for Virtex and Spartan series parts, it should give you some ideas. There is also a link to a reference design at the bottom of the pdf. There is also a very good apps note (XAPP802) covering all sorts of memory interfaces here :
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Alternatively, Xilinx have a Logicore available here :
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I hope that helps,
Best Regards
--
Steve Merritt BEng (Hons) CEng MIEE
XILINX Gold Certified Field Applications Engineer
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