33 lines
971 B
Plaintext
33 lines
971 B
Plaintext
// This file is part of www.nand2tetris.org
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// and the book "The Elements of Computing Systems"
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// by Nisan and Schocken, MIT Press.
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// File name: projects/03/a/PC.hdl
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/**
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* A 16-bit counter with load and reset control bits.
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* if (reset[t] == 1) out[t+1] = 0
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* else if (load[t] == 1) out[t+1] = in[t]
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* else if (inc[t] == 1) out[t+1] = out[t] + 1 (integer addition)
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* else out[t+1] = out[t]
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*/
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CHIP PC {
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IN in[16],load,inc,reset;
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OUT out[16];
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PARTS:
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//Inc, Rückkopplung des out und +1
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Inc16(in=toinc, out=outinc);
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//inc-flag
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Mux16(a=outtomux, b=outinc, sel=inc, out=outmuxinc);
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//load-flag, wenn 1 dann schiebe in auf das in des Registers
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Mux16(a=outmuxinc, b=in, sel=load, out=outmuxload);
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//reset-flag
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Mux16(a=outmuxload, b=false, sel=reset, out=outmuxreset);
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//Register
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Register(in=outmuxreset, load=true, out=out, out=toinc, out=outtomux);
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}
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