Section 1
Computers with one central processor
The computers with one Pc and no Pio's control T and Ms in either of two ways. First, the Pc contains the K for T and Ms; second, a separate K controls a data transmission while Pc initializes the K. In the latter case, a K is like a P where each instruction is received from Pc instead of being fetched automatically by K itself.
The Whirlwind I computer
Whirlwind (Chap. 6) controls data transmissions between Ms or T and Mp by using Pc. Thus, arithmetic and input/output processing concurrency is difficult to achieve. The structure is first discussed in Part 2, Sec. 1, page 90.
The SDS 910-9300 series
The SDS 910-9300 series is presented in Chap. 42 and is discussed in Part 6, Sec. 2, page 542. The input/output and the interrupt system are especially interesting.
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