摘要 |
In a data processing system, a plurality of prefetch elements are provided for prefetching instructions from a group of memory arrays coupled to each prefetch element. A plurality of instruction words are sequentially stored in each group of memory arrays coupled to each prefetch element. In response to a selected prefetch element receiving a prefetch token, the selected prefetch element sequentially recalls instruction words from the group of memory arrays coupled to the selected prefetch element. Thereafter, the selected prefetch element transfers the sequence of instruction words to a central processing unit at a rate of one instruction word per cycle time. In response to a forthcoming conditional branch instruction, a plurality of prefetch elements may initiate instruction fetching so that the proper instruction may be executed during the cycle time immediately following the conditional branch instruction. By coupling a group of memory banks to each prefetch element, and limiting the location of branch instructions to the last memory bank in the group of memory banks, the number of prefetch elements required to implement a data processing system having substantially similar performance to the prior art architecture is reduced. In an alternative embodiment, video memories are utilized to store instruction words, and provide such instruction words to the CPU at the rate of one instruction word per cycle time.
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