// This file is part of www.nand2tetris.org
// and the book "The Elements of Computing Systems"
// by Nisan and Schocken, MIT Press.
// File name: projects/03/b/RAM4K.hdl

/**
 * Memory of 4K registers, each 16 bit-wide. Out holds the value
 * stored at the memory location specified by address. If load==1, then 
 * the in value is loaded into the memory location specified by address 
 * (the loaded value will be emitted to out from the next time step onward).
 */

CHIP RAM4K {
    IN in[16], load, address[12];
    OUT out[16];

    PARTS:
    // Put your code here:
    DMux8Way(in=load, sel=address[9..11], a=toRAM512A,
                                          b=toRAM512B,
                                          c=toRAM512C,
                                          d=toRAM512D,
                                          e=toRAM512E,
                                          f=toRAM512F,
                                          g=toRAM512G,
                                          h=toRAM512H);

    RAM512(in=in, load=toRAM512A, address=address[0..8], out=fromRAM512A);
    RAM512(in=in, load=toRAM512B, address=address[0..8], out=fromRAM512B);
    RAM512(in=in, load=toRAM512C, address=address[0..8], out=fromRAM512C);
    RAM512(in=in, load=toRAM512D, address=address[0..8], out=fromRAM512D);
    RAM512(in=in, load=toRAM512E, address=address[0..8], out=fromRAM512E);
    RAM512(in=in, load=toRAM512F, address=address[0..8], out=fromRAM512F);
    RAM512(in=in, load=toRAM512G, address=address[0..8], out=fromRAM512G);
    RAM512(in=in, load=toRAM512H, address=address[0..8], out=fromRAM512H);

    Mux8Way16(sel=address[9..11], out=out, a=fromRAM512A,
                                           b=fromRAM512B,
                                           c=fromRAM512C,
                                           d=fromRAM512D,
                                           e=fromRAM512E,
                                           f=fromRAM512F,
                                           g=fromRAM512G,
                                           h=fromRAM512H);
}