09-14-2019 07:20 PM
I'm bit long time beginner.
I want to create multi-CPU core FPGA by possible core switch.
I want to allow to give amount of RAM for all cores in their address space - so from 64kB up to 4GB.
But I want to backup RAM content at power-off - so it can be address space for each - if possible.
It needs at least 4GB RAM - no matter what a RAM type to use, fastest core clocking is 50MHz, so it needs no any DDR4 or so fast memory type.
I want to have also Flash for storing anything like BIOS or hypervisor. Memory type can be in addon modules, eMMC, SODIMM or other. Not SD card or other alternative 'cause I need at power-off backup RAM as fast as possible.
FPGA IO have not so high requirements and I know that lot of FPGA models have more than req'd 44-pin IO. Existing RTC and/or ethernet can be benefit.
I cannot find FPGA capable to use and it is also for price range - I'm not limited by price, only need to find best performance/price ratio.
So, I think main problem is in RAM size.
Can anybody help me to decide for exact model? I hope this thread will not become forgotten.
Thank you all and community for each help, reply, comments or each suggestion, or at least words.
09-15-2019 04:48 AM
It looks like the ZCU104 might do the job nicely for you. It's got 2GB RAM included (connected to the ARM processing system), but there's also a SODIMM slot that attaches to the programmable logic. It looks like it'll support up to 8GB SODIMMs (specific models). It'll be DDR4, but you don't really have much choice - nobody makes big-and-slow RAM.
In terms of making it non-volatile, there's QSPI flash and a slot for an M.2 SSD. Using the QSPI for your FPGA bitstream would make sense, and then the SSD can handle your RAM backup (much faster, and much more capacity).
09-15-2019 07:39 AM
Ok, looks great - all benefits.
Q is simple - I'll search, but maybe you can answer me search entry: SODIMM I think is not form factor for Optane NVRAM, but - can be supported Optane in future or even - present?
Thank you very very much!