The popular Arduino boards run at something like 16MHz, and apparently have a standard interface for external SRAM. For $25 you can get a half-megabyte SRAM expansion card - it uses 12ns SRAM and cycle time seems to be 4 cycles. Or a smaller one for $20.





I thought it might be interesting to consider using this interface and form factor for 6502 or similar projects.

http://ruggedcircuits.com/html/megaram.html
http://ruggedcircuits.com/html/quadram.html

A DIY design including PCB design files and links to relevant datasheets:
http://andybrown.me.uk/wk/2011/08/28/51 ... ga-design/

A 12ns 512kbyte SRAM: http://uk.mouser.com/Search/Refine.aspx ... 096A-12JCN

Edit: I should add that the memory expansion bus only offers 16 address bits, so these are necessarily banked designs with 64k banks.

(I should mention also Garth's memory module, based on eight 10ns Cypress CY7C1049D-10VXI 512Kx8 5V SRAMs and offering 4 Mbytes. See http://wilsonminesco.com/WM-1_4Mx8SRAMm ... -15-13.pdf)

Yes, thankyou, and if you want to save money and don't need the whole 4 megabytes, they don't have to be fully populated-- although there would hardly be any point in using one with only one or two ICs on it. I have the sockets for them too, both soldertail and wire-wrap, although the wire-wrap ones are super expensive. They cost me $11 each!

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http://WilsonMinesCo.com/ lots of 6502 resources
The "second front page" is http://wilsonminesco.com/links.html .
What's an additional VIA among friends, anyhow?