Page 204 - Make Your Own PCBs with EAGLE from Schematic Designs to Finished Boards

FIGURE 8-4 Full schematic.

Once all the nets have been wired up, the schematic should look like Figure 8-4.
Sometimes, in a schematic, it is not practical to connect both ends of a net with a line. For

example, in Figure 8-4, the link between the Arduino pin A0 and the buzzer, JP1, and the apostrophe
cathode are a long way apart. I could have drawn a line between the two areas of the schematic, but
instead I have used the Label tool. To do this, you need to

• Make both ends of the net be the same net by setting them to the same name with the Name tool.

I called them A0 after the Arduino pin.
• Make a short length of net just going to a blank area on the schematic, where we are going to
add a label. Do this for both ends of the net.

• Select the Label tool, and then click on the end of the net segments you have just made to add
the labels.

We should also set up a couple of net classes to set desired track widths when we come to run the
autorouter. Open the net class editor from the Edit → Netclasses menu item, and set the default
netclass width to be 12 mils. Add another netclass (Nr 1) called “Power,” and set the width to be 24
mils (Figure 8-5).