### Step 1: schematics

The schematics is usually the single source of all logical information: footprints, element refdes and values and connections (networks or nets). A project is just a directory that holds at least the schematics, but usually also the pcb layout file and scripts.

Start the new project by creating an empty directory. Start gschem with an empty design and save it in the project directory. Place the following symbols and edit/add these attributes:

- 7805, footprint=TO220, refdes=U1
- connector-3-2, footprint=connector(3,1), refdes=CONN1
- connector-2-2, footprint=connector(2,1), refdes=CONN2
- capacitor-2, fooptrint=rcy(200), value=47uF, refdes=C1
- capacitor-1, fooptrint=0805, value=100nF, refdes=C2
- capacitor-2, fooptrint=0805, value=100nF, refdes=C2
- gnd-1

Arrange and connect the pins as shown below.

Save the design as 7805.sch.

### Step 2: build script

We are going to use a Makefile in this example to demonstrate how to automate certain steps. In a fully automated project all data exchange between the various tools (schematics editor, pcb-rnd, simulators, etc.) is done by scripts. Generating the documentation and exporting various other output like gerbers are usually automated the same way. (As an alternative, all these can be done manually, from the GUI as well.)

Create a new file called Makefile and edit it using your favorite text editor to the following:

    7805.lht: 7805.sch
    	gsch2pcb-rnd -m import 7805.sch

    clean:
    	rm -f 7805.cmd

The first rule calls the forward annotation utility, gsch2pcb-rnd to create a forward annotation command file called 7805.cmd when the schematics file is newer than the layout file (7805.lht). The second rule removes such a command file to make the directory clean of auto-generated temporary files.

### Step 3: Create the initial board

The layout process usually starts when there's at least a partially finished schematics is available. The most common workflow is that changes and improvements in the schematics are forward annotated to the layout.

Start pcb-rnd. This will load the system-installed template board as a new, empty design. Save it in the project directory as 7805.lht.

Start a shell (but don't close pcb-rnd); in the project directory, type `make`. This will create 7805.cmd that contains a pcb-rnd action script that can sync a board to the information extracted from the schematics.

Back in pcb-rnd, type ":ExecuteFile(7805.cmd)" and press enter. The colon will open the CLI entry where the ExecuteFile(filename) is an action that will load the file named and execute each line as an action.

At the end of the process, the layout should have all footprints. Press 'o' and the logical connections will show up as a "rats nest".

### Step 4: Lay out the board

Move the elements around. Pressing 'o' after some moves will re-optimize the rats. As rats nest gets simpler and simpler, this can help choosing the best placement. All components started out on the component (top) side. Hover the mouse over the 0805 capacitors and press 'b' - this will send them to the solder side.

After the placement, pick the solder layer to draw on and use the line tool to draw the traces. Change the style to 'Power' or 'Fat' to get wider traces. Press 'o' after drawing a few connections. When only the ground network is left, use the rectangle tool to draw a large polygon on the solder-gnd layer. Use the thermal tool to connect pins to the ground polygon. The thermal tool does not work on SMD pads, they need to be connected using lines.

When everything is connected, pressing 'o' will remove the last rat line. The message log window also shows how many rats are remaining when 'o' is pressed. The message log can be opened using the Window/Message Log menu.

### Step 5: updates