To transfer RAM data from the RAM Content Manager to test equipment, use MEM files. RAM contents are first organized into the logical layer, and then reorganized to fit the hardware layer. Then the contents are stored in MEM files that are read by other systems and used for testing.
The MEM files are named according to the logical structure of RAM elements created by the
configurator. Using this method, the highest order RAM blocks
are named CORE_R0C0.mem, where “R” stands for
row and “C” stands for column. For multiple RAM blocks, the
naming continues with CORE_R0C1, CORE_R0C2, CORE_R1C0, and so
on.
Data intended for RAM is stored as ASCII 1s and 0s within the file. Each memory address occupies one line. Words from logical layer blocks are concatenated or split to make them fit efficiently within the hardware blocks. If the logical layer width is less than the hardware layer, two or more logical layer words are concatenated to form one hardware layer word. In this case, the lowest bits of the hardware word comprise the lower address data bits from the logical layer. If the logical layer width exceeds the hardware layer, the words are split, with the lower bits placed in lower addresses.
If the logical layer words do not fit cleanly into the hardware layer words, the most significant bit of the hardware layer words is not used and defaults to zero. This is also done when the logical layer width is 1 to avoid left over memory at the end of the hardware block.