The SPI RAM is a 128 kilobyte RAM chip that is integrated into the UZENET expansion card, or in newer Uzebox revisions, the standard PCB itself. Its primary benefits are a large infinitely re-writable memory space that has somewhat better performance than SD. It is expected to be very useful in network programs or any place where large amounts of data need to be manipulated and not use up the finite write cycles of the SD card life span.
The Uzebox does not support having SPI RAM installed on the UZENET expansion alongside having SPI RAM installed on the motherboard. Commenting on this on the Uzebox forums, Uze said:
"you would have two chips trying to use the same lines at the same time. The MOSI line (mcu->ram) would address both at the same time but the MISO (ram->cpu) lines of the chips would conflict for sure and it could perhaps damage the chips."
The SD card interface can interfer with the SPI RAM. This occurs after flashing a game from the bootloader. The trick to fix this is to initialize the SDCard interface. Use CunningFellows's sdBase (which is already part of the master kernel), and do a simple sdCardInitNoBuffer() before going on to the SPI RAM.