LatchElm.java

import java.awt.*;
import java.util.StringTokenizer;

class LatchElm extends ChipElm {
    public LatchElm(int xx, int yy) { super(xx, yy); }
    public LatchElm(int xa, int ya, int xb, int yb, int f,
		    StringTokenizer st) {
	super(xa, ya, xb, yb, f, st);
    }
    String getChipName() { return "Latch"; }
    boolean needsBits() { return true; }
    int loadPin;
    void setupPins() {
	sizeX = 2;
	sizeY = bits+1;
	pins = new Pin[getPostCount()];
	int i;
	for (i = 0; i != bits; i++)
	    pins[i] = new Pin(bits-1-i, SIDE_W, "I" + i);
	for (i = 0; i != bits; i++) {
	    pins[i+bits] = new Pin(bits-1-i, SIDE_E, "O");
	    pins[i+bits].output = true;
	}
	pins[loadPin = bits*2] = new Pin(bits, SIDE_W, "Ld");
	allocNodes();
    }
    boolean lastLoad = false;
    void execute() {
	int i;
	if (pins[loadPin].value && !lastLoad)
	    for (i = 0; i != bits; i++)
		pins[i+bits].value = pins[i].value;
	lastLoad = pins[loadPin].value;
    }
    int getVoltageSourceCount() { return bits; }
    int getPostCount() { return bits*2+1; }
    int getDumpType() { return 168; }
}