Hi, I'm using the ROACH 1 DRAM for a lookup table for waveform generation with the DAC. Everything has been working well and as I expected, until I tried to use more than 256 MB. It looks like the ROACH has a single sided 1 GB DRAM module in the FPGA DRAM slot, but I don't have the exact part number (it came as shipped from Mo). I figured I might only be able to use 512 MB because of the caveat listed on the DRAM wiki page: "Many ROACHs have been shipped with 1 GB dual rank DIMMs by default. The current DRAM controller is not able to handle multiple ranks, so when a dual-rank DIMM is installed on the board, only half the memory is available. In order to use the full 1 GB, a single rank DIMM is needed, or in principle a dual rank 2 GB module."
But I was surprised to have issues passed 256 MB. Has anyone seen anything like this before? Is it a known issue? Thanks, Glenn
