Posted on March 19, 2013 at 15:17The data manuals are pretty explicit about what functions escape on what pins. The FSMC uses a lot of pins. ST parts with more pins aren't instrinsically more expensive, although BGA parts tend to lead to much more expensive PCB designs.
I'd recommend you look at the fitter tools mention in the prior post, and also look at the schematics for some of ST's EVAL series boards which implement the features you want.
Consider how much memory you need, external memory is SLOW and is not cached. The STM32 may not be a good choice for high bandwidth external memory, Cortex-Mx parts are generally designed to work well with tightly coupled memory. There are STM32 parts with quite large internal flash and sram options, newer model support 2MB of flash, and external SDRAM interfaces.
