Nand2Tetris — 第 3 章
循序邏輯與記憶體
//1位元暫存器[引用:2]
//輸入:輸入,負載(1 位元)[引用:3]
//輸出:out(1 位元)[引用:4]
//操作:如果負載為 1(有效),則暫存器的值將設定為 [cite:2] 中的值。
//否則暫存器保留其目前值(如果 load(t) out(t+1) = in(t),否則 out(t+1) = out(t))[引用:3]。
CHIP Bit {
IN in, load;
OUT out;
PARTS:
Mux(a=DFFO , b=in , sel=load , out=MuxO );
DFF(in=MuxO , out=DFFO, out=out );
}
//16位元程序計數器
//輸入:in[16]、載入、inc、重置[引用:5]
//輸出:out[16] [引用:5]
//操作:根據重設、載入和inc訊號的優先權來決定下一個時脈週期的暫存器值[引用:6]。
CHIP PC {
IN in[16], load, inc, reset;
OUT out[16];
PARTS:
Inc16(in=regOut, out=incOut);
Mux16(a=regOut, b=incOut, sel=inc, out=mux1);
Mux16(a=mux1, b=in, sel=load, out=mux2);
Mux16(a=mux2, b=false, sel=reset, out=mux3);
Register(in=mux3, load=true, out=regOut, out=out);
}
//16位元暫存器[引用:34]
//輸入:in[16],載入[引用:35]
//輸出:out[16] [引用:36]
//操作:如果負載為 1(有效),則暫存器的值將設定為 [cite: 34] 中的值。
//否則,保持當前值[引用:35]。 16 位元晶片並聯[引用:36、37、38、39、40、41]。
CHIP Register {
IN in[16], load;
OUT out[16];
PARTS:
Bit(in=in[0] , load=load , out=out[0] );
Bit(in=in[1] , load=load , out=out[1] );
Bit(in=in[2] , load=load , out=out[2] );
Bit(in=in[3] , load=load , out=out[3] );
Bit(in=in[4] , load=load , out=out[4] );
Bit(in=in[5] , load=load , out=out[5] );
Bit(in=in[6] , load=load , out=out[6] );
Bit(in=in[7] , load=load , out=out[7] );
Bit(in=in[8] , load=load , out=out[8] );
Bit(in=in[9] , load=load , out=out[9] );
Bit(in=in[10] , load=load , out=out[10] );
Bit(in=in[11] , load=load , out=out[11] );
Bit(in=in[12] , load=load , out=out[12] );
Bit(in=in[13] , load=load , out=out[13] );
Bit(in=in[14] , load=load , out=out[14] );
Bit(in=in[15] , load=load , out=out[15] );
}
//八個 16 位元暫存器的記憶體 [cite: 12]
//輸入:in[16],負載,位址[3] [引用:15]
//輸出:out[16] [引用:15]
//操作:如果載入為 1,則將位址選擇的暫存器的值設定為[cite:13]中的值。
//否則,該值不會改變,並且所選暫存器的值將被傳送到 out [cite: 14]。
CHIP RAM8 {
IN in[16], load, address[3];
OUT out[16];
PARTS:
DMux8Way(in=load, sel= address,
a= Out0, b= Out1,
c= Out2, d= Out3,
e= Out4, f= Out5,
g= Out6, h= Out7);
Register(in=in , load=Out0 , out=R0 );
Register(in=in , load=Out1 , out=R1 );
Register(in=in , load=Out2 , out=R2 );
Register(in=in , load=Out3 , out=R3 );
Register(in=in , load=Out4 , out=R4 );
Register(in=in , load=Out5 , out=R5 );
Register(in=in , load=Out6 , out=R6 );
Register(in=in , load=Out7 , out=R7 );
Mux8Way16(
a= R0, b= R1,
c= R2, d= R3,
e= R4, f= R5,
g= R6, h= R7,
sel= address, out=out);
}
//64個單字記憶
//輸入:in[16],負載,位址[6] [引用:25]
//輸出:out[16] [引用:25]
//操作:將8個RAM8晶片組合成64個暫存器[引用:26,27,28]。
CHIP RAM64 {
IN in[16], load, address[6];
OUT out[16];
PARTS:
DMux8Way(in=load, sel=address[3..5], a=loadA, b=loadB, c=loadC, d=loadD, e=loadE, f=loadF, g=loadG, h=loadH);
RAM8(in=in, load=loadA, address=address[0..2], out=outA);
RAM8(in=in, load=loadB, address=address[0..2], out=outB);
RAM8(in=in, load=loadC, address=address[0..2], out=outC);
RAM8(in=in, load=loadD, address=address[0..2], out=outD);
RAM8(in=in, load=loadE, address=address[0..2], out=outE);
RAM8(in=in, load=loadF, address=address[0..2], out=outF);
RAM8(in=in, load=loadG, address=address[0..2], out=outG);
RAM8(in=in, load=loadH, address=address[0..2], out=outH);
Mux8Way16(a=outA, b=outB, c=outC, d=outD, e=outE, f=outF, g=outG, h=outH, sel=address[3..5], out=out);
}
//512個單字記憶
//輸入:in[16],負載,位址[9] [引用:29]
//輸出:out[16] [引用:29]
//操作:8個RAM64晶片組合起來形成512個暫存器[引用:30,31,32]。
CHIP RAM512 {
IN in[16], load, address[9];
OUT out[16];
PARTS:
DMux8Way(in=load, sel=address[6..8], a=loadA, b=loadB, c=loadC, d=loadD, e=loadE, f=loadF, g=loadG, h=loadH);
RAM64(in=in, load=loadA, address=address[0..5], out=outA);
RAM64(in=in, load=loadB, address=address[0..5], out=outB);
RAM64(in=in, load=loadC, address=address[0..5], out=outC);
RAM64(in=in, load=loadD, address=address[0..5], out=outD);
RAM64(in=in, load=loadE, address=address[0..5], out=outE);
RAM64(in=in, load=loadF, address=address[0..5], out=outF);
RAM64(in=in, load=loadG, address=address[0..5], out=outG);
RAM64(in=in, load=loadH, address=address[0..5], out=outH);
Mux8Way16(a=outA, b=outB, c=outC, d=outD, e=outE, f=outF, g=outG, h=outH, sel=address[6..8], out=out);
}
//4K字記憶
//輸入:in[16],負載,位址[12] [引用:7]
//輸出:out[16] [引用:7]
//操作:8個RAM512晶片組合起來形成4096個暫存器[引用:8、9、10]。
CHIP RAM4K {
IN in[16], load, address[12];
OUT out[16];
PARTS:
DMux8Way(in=load, sel=address[9..11], a=loadA, b=loadB, c=loadC, d=loadD, e=loadE, f=loadF, g=loadG, h=loadH);
RAM512(in=in, load=loadA, address=address[0..8], out=outA);
RAM512(in=in, load=loadB, address=address[0..8], out=outB);
RAM512(in=in, load=loadC, address=address[0..8], out=outC);
RAM512(in=in, load=loadD, address=address[0..8], out=outD);
RAM512(in=in, load=loadE, address=address[0..8], out=outE);
RAM512(in=in, load=loadF, address=address[0..8], out=outF);
RAM512(in=in, load=loadG, address=address[0..8], out=outG);
RAM512(in=in, load=loadH, address=address[0..8], out=outH);
Mux8Way16(a=outA, b=outB, c=outC, d=outD, e=outE, f=outF, g=outG, h=outH, sel=address[9..11], out=out);
}
//16K字記憶體
//輸入:in[16],負載,位址[14] [引用:22]
//輸出:out[16] [引用:22]
//操作:四個RAM4K晶片與DMux4Way和Mux4Way16結合配置16384個暫存器[引用:23, 24]。
CHIP RAM16K {
IN in[16], load, address[14];
OUT out[16];
PARTS:
DMux4Way(in=load, sel=address[12..13], a=loadA, b=loadB, c=loadC, d=loadD);
RAM4K(in=in, load=loadA, address=address[0..11], out=outA);
RAM4K(in=in, load=loadB, address=address[0..11], out=outB);
RAM4K(in=in, load=loadC, address=address[0..11], out=outC);
RAM4K(in=in, load=loadD, address=address[0..11], out=outD);
Mux4Way16(a=outA, b=outB, c=outC, d=outD, sel=address[12..13], out=out);
}