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所以,我基本上需要创建一个 PC.hdl,但从 x2 8 位寄存器开始。这是起点:

// This file is BASED ON part of www.nand2tetris.org
// and the book "The Elements of Computing Systems"
// by Nisan and Schocken, MIT Press.
// File name: project03starter/a/PC.hdl

/**
 * A 16-bit counter with load and reset control bits.
 * if      (reset[t] == 1) out[t+1] = 0
 * else if (load[t] == 1)  out[t+1] = in[t]
 * else if (inc[t] == 1)   out[t+1] = out[t] + 1  (integer addition)
 * else                    out[t+1] = out[t]
 */

CHIP PC {
    IN in[16],load,inc,reset;
    OUT out[16];

    PARTS:
    // Something to start you off: you need *two* 8-bit registers
    Register(in=nextLow,  out=out[0..7],  out=currentLow,  load=true);
    Register(in=nextHigh, out=out[8..15], out=currentHigh, load=true);

    // Handling 'inc' to increment the 16-bit value also gets tricky
    // ... this might be useful
    And(a=inc, b=lowIsMax, out=incAndLowIsMax);
    // ...

    // The rest of your code goes here...
} 

我知道如何通过仅处理 16 位来正常执行此操作,但我不确定如何使用 8 位寄存器来解决此问题。

任何人都可以帮助我正确的解决方案吗?

谢谢。

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1 回答 1

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假设您有一个 8 位加法器,您可以使用 2 个加法器实现 16 位增量器,其中一个计算 currentLow+1,另一个计算 currentHigh+(低位加法器的进位输出)

于 2020-10-21T01:07:46.130 回答