Description: Here at SparkFun, we refuse to leave ‘good enough’ alone. That’s why we’re adding to our line-up of Arduino-compatible microcontrollers once more! The Pro Micro is similar to the Pro Mini except with an ATmega32U4 on board. The USB transceiver inside the 32U4 allows us to add USB connectivity on-board and do away with bulky external USB interface.
This tiny little board does all of the neat-o Arduino tricks that you’re familiar with: 9 channels of 10-bit ADC, 5 PWM pins, 12 DIOs as well as hardware serial connections Rx and Tx. Running at 16MHz and 5V, this board will remind you a lot of your other favorite Arduino-compatible boards but this little guy can go just about anywhere. There is a voltage regulator on board so it can accept voltage up to 12VDC. If you’re supplying unregulated power to the board, be sure to connect to the “RAW” pin on not VCC.
This latest revision corrects the silk error from the last version of the board so that pin 14 is correctly labeled. We’ve also added a PTC fuse and diode protection to the power circuit and corrected the RX and TX LED circuit.
Not sure which Arduino or Arduino-compatible board is right for you? Check out our Arduino Buying Guide!
Based on 37 ratings:
1 of 1 found this helpful:
I needed something small with USB onboard to control a strip of NeoPixels.
My project uses a small C# program to communicate over serial with the Arduino which drives the pixels. I wanted something small and this was the only Arduino I could find to fit the bill. The trinket doesn’t have serial and the pro mini would tie up my programmer.
That being said, I have had some issues with this showing up in the device manager and for that reason I don’t think I would have this as my only arduino. I think your best bet would be to prototype with something like a RedBoard and port your over to this little guy. If I have another project that needs serial communication or USB power I would definitely use one of these. Otherwise I would probably go with a Pro Mini if I needed a small dedicated arduino to stick in a project.
1 of 1 found this helpful:
I’m using this and the 3.3V version (in separate boxes) to control a few sensors (some of which are 5V, others are 3.3V). They both work just fine; however, be careful when programming to have BOTH the board and processor set correctly under the Arduino Tools menu. My very first use of one of these was with the wrong processor (I had a 3.3V pro-micro, but tools->processor was set to 5V); and the board was bricked after programming.
Admittedly, it was my bad, but it would be nice if Arduino and the bootloader could handshake to verify that the correct settings were used and at least post a warning to the user.
You’re right, care definitely needs to be taken to make sure that both Board and Processor are set correctly. There are ways to un-brick the unit, though they can take some time and effort. Take a look at the comments from one of our techs, here: https://www.sparkfun.com/products/12640#comment-55dde917757b7f86028b4567. Happy Hacking!
2 of 2 found this helpful:
I am a retired engineer and have been out of the software business for almost 10 years. I purchased the Pro Micro after reading up on the Arduino products and capabilities. I have been playing with the Pro Micro for about a week and have two projects well along in the design cycle. I really appreciate how easy it is to prototype with the Pro Micro and it has some very nice features. The Arduino IDE is a very nice way to develop software too! Sparkfun has some excellent documentation and examples. This has really helped the process of getting back into programming. Thank you Sparkfun!
I love the small form factor and native USB support.
Using these small boards in an embedded data acquisition system. The one main bugbear is the USB connector, which we use for data upload and parameter setting on the board. If the board is fitted inside a casing, getting the USB connection externally is at times frustrating. We can’t always have the USB connector poking out the side of the enclosure and fitting an extension cable is cumbersome in small cases. It would be useful if a version is offered with a 6 pin header connection for connection to an extension cable, 6-pin to USB-Micro
I’ve been helping my teenage daughter last few weeks putting together a school project for automated indoor pot plant watering, using a sparkfun soil moisture detector. Getting power consumption down as low as possible has been a challenge, but we have had reasonable success. We drive it off a small garden light solar cell and one AA rechargeable battery via a Pololu boost regulator. I took off the power LED resistor and bypass the input regulator; with the Pro Micro asleep and the boost regulator shut down it consumes very little current. (The official safe operating area at 16MHz is down to 4.5V, but I found it works fine down to 4V).
A number of gotchas which took some time to figure out… 1. Nearly always have to load sketches via the double reset technique to use the bootloader mode; it is a challenge to get the upload timing right since the bootloader mode only gives you an 8 second window. 2. The Arduino digitalPinToInterrupt(pin) function does not map to the correct interrupt number using the pin number as printed on the silkscreen; I had to go by the sparkfun documentation instead.
I prototyped with the Red Board Arduino and Proto Shield. I fabricate my device with the Pro Micro. I liked the smaller size. The code was of course the same and performance was the same.
Purchased this to handle head tracking for a graduate project, worked out great.
0 of 1 found this helpful:
If you are thinking of buying this board, get a Pro Mini and the FTDI board instead. The Pro Mini is half the price, and the FTDI board can be reused.
The Pro Micro is too finicky. At some point you will mess up a setting in the Arduino IDE. With many other boards that’s not a problem and can be easily fixed. Not so with the Pro Micro. The bootloader is configured to get out of the way quickly, and if you program the board incorrectly, you must perform magic tricks to get the board back to life.
I played with mine for about 20 minutes, and for some reason the Arduino IDE decided to change to the 3.3v version of the board; I swear I did not change anything myself. Programming the 5v board using the configuration for the 3.3v version bricks the board. Sparkfun’s website describes the magic tricks you must perform, but after 20 minutes I said the heck with it.
I tossed it in the trash and ordered a Pro Mini instead. If you have a lot of patience or $19.95 is a lot of money for you, you might spend more time getting your bricked Pro Micro back to life. I’d rather spend my time doing something else.
Allowed me to program a start button for my car!
I had a great deal of difficulty getting a sketch uploaded. The tweaking you have to do to the IDE is pretty straight forward and well documented (thanks Sparkfun!) but I kept having issues with the bootloader and being able to upload my sketch. I ended up not using the Micro because it was too frustrating to work with when I have other things to troubleshoot. Ended up using a Nano from one of my other projects.
Just fine no problems yet.
There are many different Arduino platforms out there, some better suited than others for specific projects, but I’ve never found one as versatile as this little bugger. USB HID support is one of its biggest advantages, but it’s small size make it perfect for prototyping compact solutions. Only issue I had was a self inflicted problem where I flashed with the wrong board voltage/frequency selected, causing the bootloader to flake out, but a reset using the Sparkfun directions got me all sorted out.
Micro usb is a huge plus for powering projects with rechargeable cell phone power supplies. Built in ftdi to serial interface means you can power and configure with one standard cable. I only use SparkFun’s arduino clones for this reason.
USB + Arduino in compact size this is the best.
The Pro Micro - 5V/16MHz is a very compact, low-cost, and very effective product.
Only had a little trouble connecting it to my laptop. Had to reset it twice, then upload a sketch within 8 seconds to connect it to my laptop. When I had that figured out, everything worked without problems.
I use these little arduino boards for all kinds of stuff…drag racing transmission controllers to led sign controllers to frequency agile signal generators. The small footprint and on-board USB make it a breeze to use for rapid prototyping.
0 of 1 found this helpful:
If I compile code for the Arduino Uno, it compiles to 5.1kB. If I simply switch the device to SparkFun Pro Micro 5V/16MHz, it bulks up to 8.8kB. Any explanation?
Sorry for the delay in the answer - but the larger compilation size is due to the bootloader for this board (it differs from the Uno).
Took a while to download my program, kind of frustrating but eventually I got my timing right.
It does do what I programmed it to do - using it with a ZX gesture sensor to act as a mini-keyboard-like input to a Rpi for a magic mirror project.
I would buy this again.
I use a the Macbook Pro with OS X. Was major pain getting the drivers set up so I could download a sketch. SparkFun warns that the USB can be difficult. I almost gave up. Still cannot get Serial Port Com to operate. USB is finally working enough for my needs. But board is amazingly small and fits in my small enclosure with a OLED. Needs more debugging on the boot loader to be 100% easy to use. I would not have used the product had I known the boot loader would be so much trouble. Come on Sparkfun, put a few more debug hours in!
I was building an interface for a project and had used an Arduino Mega for the prototype. I decided I wanted something considerably smaller for the final project and this fit the bill. A couple pin remapping in code and I had this thing up and running in minutes. It works great!
Works great! Additionally SparkFun support is top notch when I had a slight issue.
0 of 1 found this helpful:
I never figured out how to make it work with the Arduino IDE. Don’t know why. I gave up and used a ProMini instead.
Be sure to follow along in the Hookup Guide. There is an explanation of how to install on Windows, Mac and Linux. This board does require some extra steps compared to the Pro Mini. https://learn.sparkfun.com/tutorials/pro-micro–fio-v3-hookup-guide#installing-windows Happy hacking
Just started using this board and was happy to get successfully through all the driver loops and uploading the first sketch.
Was ready to move a project from a larger prototype board to this little guy.
Only if I knew that loading a second sketch will be close to impossible…
So while running, arduino can’t talk to this board, you need to double short the reset pin, and you get 8 seconds to load a new sketch before the current one starts running. Who made that poor choice? really 8 seconds?
Now that I have it up and running, this has been a little champ. Initially, though, it took a bit to get there. First I had to figure out where to get the board package from and how to install it in the Arduino IDE. It’s really not that hard to do but without decent directions, I had to fumble my way through. Then, I “soft-bricked” the board by building and uploading with the 3V/8MHz fuse settings. Ooops! My bad! Fortunately, it wasn’t hard to find instructions on how to unbrick it. Apparently, this mistake is a common one. But with those “preliminaries” out of the way, it’s been working well. If you need an Arduino in a tight package, this product is worth your consideration.
Nice quality, thanks
love the onboard USB. Only drawback is no onboard reset button. Documentation on this product as far as startup drivers etc is easily accessible. Overall great product
This does everything I need it to in a small form factor. The only issue I have with it is that the USB port wiggles a lot on the board and I’m afraid it will come off at some point. In my current project, I only use the USB to program it.
Extremely small and still had all the power I could ever need for my project.
It’s “solid” in terms of reliability, small, economical, and with onboard USB. This has really become my goto board for projects that move from the bench to a permanent installation on equipment where I don’t need a huge number of I/O lines or program space.
Just needed it to be a simple LED controller for my computer and it has been nothing but wonderful!
The Pro Micro 5V/16 MHz board has been my favorite for a long time. My hobby of electroherbalism needs specialized experimental instruments, and this module is the only one that works for most of my projects. For my current instrument design and build, some essential qualities are the precision tone frequencies - accurate to 1 Hz at least to 5,000 Hz - as compared to an Arduino Uno which produces, for example, 529 Hz when a frequency of 528 Hz is specified in tone, quite unusable. And the 5 V interface is perfect for matching with the low cost “LCD Key” common interface which provides both LCD and adequate pushbuttons for my instrument’s human interface control. And the Arduino ProtoBoard works nicely for a place to do the pin swap wiring for the Uno footprint the LCD Key needs.