ram

Hi,

you could use a 32bit bus system and an other port pin to switch between memory banks.
With one extra pin you have already a possible maximum of 2x 4G, minus peripheral memory.

But ... in the uC world - where could you need approx. 3.5G of RAM for? It's already massive for a PC, and I wounder if a uC is able to handle that...

BR,
/th.

Hi,

you could use a 32bit bus system and an other port pin to switch between memory banks.
With one extra pin you have already a possible maximum of 2x 4G, minus peripheral memory.

But ... in the uC world - where could you need approx. 3.5G of RAM for? It's already massive for a PC, and I wounder if a uC is able to handle that...

BR,
/th.

It takes a lot of RAM to run a PC simulator running Windows Vista ;)

Just a footnote: Large RAM chips are using some form of multiplexed bus, and are having quite interesting timings. And dual data rate (DDR) is most common. And dynamic memory (DRAM) also requires regular refreshes to recharge the capacitors - without the refresh, all bits will be cleared to high or low state.

To handle such memory, you need an ARM chip with a suitable memory controller. And it will the capabilities of that controller that will decide what type of memory you can use, and how easy/hard it will be to connect really large memory modules/chips.

Right now, you haven't supplied any information at all, for people to even begin helping you. We don't know what processor. We don't know about what type of memory you are thinking about. We do not know what you are planning to do with the memory - running a Linux? What needs these quantities of RAM, and how fast accesses are needed?