A couple of weeks ago, Off-The-Shelf Hacker looked to the basics of schematics. This week we’ll cover using the Fritzing application to actually draw your own schematics. I suggest drawing a few schematics by hand, just for the practice. Drawing schematics with Fritzing will certainly speed up the process. It’s a moderate learning curve that will definitely get easier and faster with practice. Fritzing is all over the place in the Maker community, making it the go-to option when you need to document your circuit design.
If you haven’t installed Fritzing yet, just follow the steps below to get going.
Download the appropriate version for your operating system. I used the Linux-64 version (download link) and it was copied into my ~/Downloads directory. I expanded the tar file and started up the Fritzing program with the following command lines.
rob% cd ~
rob% cp ~/Downloads/fritzing-0.9.2b.linux.AMD64.tar.bz2 .
Don’t forget the dot at the end of the command. That just copies it in the current directory with the same filename.
rob% tar -xvf fritz*bz2
rob% cd fritz*
Here’s what the main Fritzing screen looks like:
Start a new file by clicking “File” and “New.” By default, a blank sketch will appear, in “Breadboard” view, with a standard length breadboard and lists of parts on the right.
There are three view modes in Fritzing. Breadboard view (the default) lets you design with physical-looking components.
The schematic view shows the circuit with traditional schematic symbols.
The PCB view lets you physically arrange the components on a printed circuit board. We’ll confine our discussion today to the Schematic view, so click on that tab. As you’d expect, the three views stay synced up as you design. Be aware that you’ll frequently have to manually arrange components, in the various views to make them neat and organized. Feel free to explore the other two views, on your own.
Let’s design a basic circuit using the example from the “Reading Schematics Like A Pro” article.
Click on the “core” tab on the parts list. A bunch of standard parts for input, output and micro-controllers will appear. Scroll down to the “output” group and select the DC motor. Click and drag it over to the blank schematic sheet.
Next, move up to the “power” group of parts and select the battery. Click and drag it over to the schematic sheet.
Lastly, scroll up and find the toggle switch under “inputs.” Click and drag it onto the schematic sheet.
Arrange the parts in a neat fashion, similar to my drawing, above.
Connecting the parts is pretty straightforward. Click on the end of a component’s wire and drag the connection (wire) over to another component, hooking it up to the desired connection. For example run a wire from the negative side (short bar) of the battery to one of the wires on the motor. You’ll need to get the end of the wire pretty close to the component’s wire before it will connect. If it looks like the wire ends in space, highlight the wire end again and move it over a little until it “clicks” or “connects” to the other wire.
Wire the other side of the motor to one terminal on the toggle switch. Then, connect the other side of the toggle switch to the positive (long bar) battery connection. Of course, we always want to have a complete circuit.
Making Your Schematic Life Easier
Grabbing parts, putting them on the schematic sheet and connecting them together. That is really all there is to draw schematics with Fritzing. The magic comes with being able to find the correct parts, accounting for all the connections and making the drawing neat and tidy.
Always use the latest version. I’m using the 64-bit version, fritzing-0.9.2b. The latest version includes fairly up-to-date parts libraries from the big hardware vendors. What this means is that if you use a current version of Fritzing, you won’t have to root around the Internet to find the parts you need for your schematics.
For example, Sparkfun sells the Arduino Pro Mini. I’ve used them in a few of my projects. Scroll down and click on the Sparkfun parts tab. You’ll find the Mini in the “other” group.
You can also use the search bar, at the top of the parts list to look for parts. Type in “pro mini” and you’ll get a bunch of parts. Apparently, many of the parts have “pro mini” in their tag list. You’ll have to scroll down through the parts, a bit, to find it in the list.
What if you can’t find the part you need? Just look for an appropriate .fzz file on the Web. Fritzing parts are created by vendors and third parties, in the .fzz format and are easily imported into the application. I recently needed an ESP8266-01 part for a new wireless project. So, I searched in Google for “esp8266-01” and “fzz”. Several sites popped up. I clicked to download one of the .fzz files into my Downloads directory. The files usually aren’t very big.
To use the file, start Fritzing and click the “core” tab on the parts list. On the right side of the “Core Parts” bar, you’ll see a little configuration drop-down. Click the drop-down and select “Import”. It should be at the top of the list. Go to the directory where the .fzz was downloaded. Click on the .fzz file and it will be imported into your parts list, probably under the “mine” parts tab. Simply drag it into the schematic, as usual.
Another important tip is that you can manipulate the parts once they’re in your schematic. Left click on a part, then right-click to get a menu of things you can do to the part. For example, if the battery symbol has the positive terminal on the wrong side, just flip it horizontally (or vertically), so you can minimize long, complicated wire runs and unnecessary cross-overs. It takes a little practice to arrange parts, so the schematic is easy to read and unambiguous.
Other functions on parts include rotating it 90 degrees clockwise/counter-clockwise, raising/lowering (in front of or behind other parts) in the drawing and copying/pasting. Take full advantage of these features and make your schematics neat and tidy. People looking at the schematic will appreciate your efforts. You’ll thank yourself too when you finally cycle back around to that back-burner project you were working on a month ago.
Go Forth And Draw
Fritzing is much like most other vector-based drawing applications. Remember that you are working with objects, as opposed to bits of color and you should be fine. Explore the program a bit and take advantage of the labor saving features, to create awesome schematics.
Also, Fritzing is the perfect complement to the other important tools in the Off-The-Shelf Hacker’s tool box, like the Arduino IDE, Linux, Processing, Raspberry Pi and so on. It also has a strong following in the Maker community, so it’s as good as a standard.