A method and apparatus for performing
memory array / row scoreboarding in a dynamic access memory (
DRAM) having dual
bank access. The
DRAM of the present invention allows dual simultaneous memory accesses into a memory divided into a plurality of arrays (e.g., 48 arrays). Each array of the
DRAM contains a plurality of rows (e.g., 256). Each row of the DRAM contains storage for a certain amount of
data bits (e.g., 1024). The DRAM in one configuration contains 1.5 Megabytes of memory. During a dual
bank DRAM access, the
system allows a first access for pre-opening a row (e.g., a page) of
DRAM memory within a first array while simultaneously allowing a second access for reading / writing data to an opened row of another array aside from the first array. The present invention scoreboarding
system tracks the rows that are currently open so that immediate read / write accesses can take place. Upon presentation of a row and array, the scoreboard determines if the presented row is currently open, and if so, generates a hit
signal that allows an immediate read / write access to the presented row. If the presented row is not open, the present invention generates a miss
signal so that the row can be immediately opened before access is allowed. The scoreboard contains a memory unit containing row information for each array in the DRAM. The scoreboard, in addition to other novel features, allows an efficient DRAM configuration allowing dual memory accesses per cycle.