Minimum-Access Code Definition/Meaning:
A form of programming for early computers with magnetic-drum
storage. It was also known as optimum programming. In programs for this kind of
machine, each instruction specifies the address of its successor, and it is
desirable to place instructions in addresses so chosen that they are available
under the reading heads when required. Since the execution time of instructions
varies, it was necessary to work out how far the drum would rotate during
execution of an instruction: this then determined the optimum position of its
successor. Since this address might already be occupied, obtaining an optimal
(or nearly optimal) distribution of instructions on the drum was extremely
difficult.
The most widely used machine of this kind was the IBM 650; the success of the
machine was largely due to the SOAP assembler, which produced near-optimal code
positioning without any special effort on the part of the programmer.
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