Hello,
I thought that I could ask for advices on this group since most high-end embedded CPU have the same constraints.
I would like to add a good RAM capacity to existing evaluation/development boards equiped with 2.54mm pins. Ideally that would mean 32 or 64MB with a 16-bit datapath (32-bit would be too wide, too many wires...). SRAM are not possible, the largest I have are 36Mbits in BGA, this is not suitable for a first prototype. And using/hacking a SODIMM is not suitable either because they are 64-bit wide.
I also have SDRAM chips that fit the description, like PC133 compatible 256Mbits SSOP with 8-bit or 16-bit wide bus. However, I don't feel like making a PCB for just 1 or 2 chips. There is still the old hack of wiring the pins with fine wires but the chips are very fine pitch (.65mm) and it's going to be difficult...
Is there another method ?
Oh, and once the chips are wired (a pair of 256Mb will give 64M bytes), how does one initialises and uses these complex beasts ?
yg