DACElm.java

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

class DACElm extends ChipElm {
    public DACElm(int xx, int yy) { super(xx, yy); }
    public DACElm(int xa, int ya, int xb, int yb, int f,
		  StringTokenizer st) {
	super(xa, ya, xb, yb, f, st);
    }
    String getChipName() { return "DAC"; }
    boolean needsBits() { return true; }
    void setupPins() {
	sizeX = 2;
	sizeY = bits > 2 ? bits : 2;
	pins = new Pin[getPostCount()];
	int i;
	for (i = 0; i != bits; i++)
	    pins[i] = new Pin(bits-1-i, SIDE_W, "D" + i);
	pins[bits]   = new Pin(0, SIDE_E, "O");
	pins[bits].output = true;
	pins[bits+1] = new Pin(sizeY-1, SIDE_E, "V+");
	allocNodes();
    }
    void doStep() {
	int ival = 0;
	int i;
	for (i = 0; i != bits; i++)
	    if (volts[i] > 2.5)
		ival |= 1<<i;
	int ivalmax = (1<<bits)-1;
	double v = ival*volts[bits+1]/ivalmax;
	sim.updateVoltageSource(0, nodes[bits], pins[bits].voltSource, v);
    }
    int getVoltageSourceCount() { return 1; }
    int getPostCount() { return bits+2; }
    int getDumpType() { return 166; }
}