I just began the design of a system based on the NS7520. I intend to use a 32bit 128Mbit SDRAM and a 16bit 16MBit flash memory. After searching for reference designs and always watching on the dev kit schematic, i think there’s some imformation missing. In this forum i read the first time, that 16bit devices should be attached to D16:31 instead of D00:15, which would be normally assumed (Forum text: for 16 bit device use D16-D31 (HW manual page 1-15). Unused D0-D15 should be pulled up with 10k resistors). I have a NS7520 data sheet, a NS7520 Hardware Reference and a NS7520 Jumpers and Components Guide of the dev kit. What is ment with “HW manual”? I searched all of your webpage and every CD coming with the dev kit. I would appreciate any hint, where I can get additional information about attaching devices to busses and/or a reference design of a simple architecture with as few components as possible. Thanks Christian
I think this is a reference to the old Net+50 manual (document INTERNATIONAL) which talks about the data bus and port sizes in section 1 around about page 15… and the section probably did the same in the Net+40 manual as well… Either way the talk about pull ups I think is misleading as I believe it only applies to the devices before the NET+50 (and only then in reference to address lines I think?)… i.e. after the NET+50 these external pullups are not required. As for info/reference designs on hooking up memory to these chips… there isn’t much available… That old manual has some stuff and the new one (for the NET+50) has some info in the memory controller section… Other than that its the reference schematics for the dev kits… Regards, Dave
That should have been 8833242A dated June 2001 and not INTERNATIONAL… why the spell check thought that was the word… and why I pressed change I have no idea 
Thank you! The Net+50 has also been changed and obviously these parts have been removed. In the Net+15/+40-Manual I found the mentioned chapter and I hope, I can use most of the information for the NS7520. Anyway, I would be happy if Netsilicon would provide a reference design with parts, that almost everyone has to implement into a new design (32Bit or 16+16Bit SDRAM, 16Bit or 16+16Bit Flash, Phy).
Hi Christian If you want a 16+16 bit SDRAM + 16 bit Flash references design (admittedly using a NET+50) then FS Forth-Systeme does a devboard that has a robust memory interface providing 64Mb CAS2 SDRAM (2 * 16bit * 2M) and 8Mb of Flash (16bit * 4M). See if you can get hold of the schematic (Modnet50 rev 2)from their web site… and I think they also do a NS7520 dev board as well… www.fsforth.de Regards, Dave