How to use SDRAM on de2-70 board?

first of all.

why not using SOPC?

the reason I guess is to access SDRAM via NiosII is too slow.

you wanna access SDRAM as fast as it can.

is that right?

you can use SOPC builder and Avalon-MM "Master".

you can use bast transfer via Avalon bus.

this is easy way and safety way.

otherwise, you need to write long long code in HDL.

like this.

ttp://cache.micron.com/protected/expiretime=1282712493;badurl=ahr0cdovl3d3dy5tawnyb24uy29tly80mdquahrtba==/fe03e95c6f6a764e10b3fbfff5a207f7/1/32/512mb_sdr.pdf

reading and writing process is not difficult.

but you need to write initial process and precharge process as well.

I have done this before( for SDRAM / DDRSDRAM)

it took months.( I was newbie too)

now, I was studied I did not need to write this.

SOPC is handy enough.

if you still wanna try it, the hell is waiting for you.

good luck.