forums.ps2dev.org

whats the difference between
sd flash cards like the ones for cameras
and the "duo" flash cards for the psp?
can you use a normal sd flash card with your psp or does it have to be one of these duo cards?

The difference is the size. If there is some type of converter, then I think it will work, but that is the primary difference.

The difference is the same sort of different as between a compact flash card and a sony memory stick. They are different size, different form facter, different connector, different specs, different interface... in other words, they are just very different ;)