Documentation from Altera:

Go to their literature page: http://www.altera.com/literature/lit-nio2.jsp

Click on (zipped) Embedded Documentation One-Click Download for the version of Quartus you have.Install this in a folder for future reference.These are your only documents about how to add memory.

 

Memory chips on the DE2 Development Board

This board is made by Terasic

http://www.terasic.com.tw/cgi-bin/page/archive.pl?Language=English&CategoryNo=53&No=30

 

Flash memory is a 4MB chip by Spansion: S29AL032D.††

Company webpage and data sheets: http://www.spansion.com/Products/Pages/ProductDetails.aspx?ProdID=S29AL032D

 

SRAM 512 KB is by ISSI Integrated Silicon Solution, Inc.website: www.issi.com

Part # IS61LV25616AL-10TL†† Search of company database turns up several similar chips, closest chip is IS61LV256ALÖ http://www.issi.com/pdf/61LV256AL.pdfThis is a Low Voltage high speed CMOS.The *.pdfstates itís a 32K x 8 and interprets that to mean 32,768 word by 8 bit static RAM.Based on the DE2 board label, 512 KB and the 16 in the part # we could assume that this is a 32K x 16 or 32,768 word by 16 bit static RAM.There is other good info in the PDF about the control lines.

SDRAM 8MB is by PSC Powerchip Semiconductor Corporation www.psc.com.tw/english

Part #A2V64S4OTCPwebsite link to SDRAM chips: http://www.psc.com.tw/english/product/product_1c.html††

Things change fast in this business, company is now called Powerchip Technology Corporation.