Last year I got an Arduino Yún to try out. The Yún is Wow. It became my favourite microcontroller the second I powered it up. The only real downside of the Yún being price, coming in at around $85 USD, it certainly wasn’t cheap. For my current project I thought I would try out the Arduino Ethernet. It is a fair bit cheaper (I got it for about half the price of a Yún from Seeed), and I didn’t need wifi on this particular project. So how did the Arduino (Seeeduino) Ethernet stack up?

Picture of Seeeduino Ethernet mounted in 3D printed case

FTDI breakout

The first downside of the Arduino Ethernet design (regardless of manufacturer) is how they made room for the network port. Arduino dropped the USB connector and FTDI USB-to-serial chip from the board. So uploading your sketches is via a FTDI-style USB-to-serial breakout board. This connector is not included, and you buy it separately. No big deal. But if you don’t have one, it will add about $17 to the cost of your project.

Limited PWM pins

The second design downside is the limited number of PWM pins. The Arduino Ethernet only has four pins with PWM, while pins 10, 11, 12 and 13 are reserved for interfacing with the Ethernet module. The documentation suggests you shouldn’t use them. I’m not sure whey they even included headers for these unusable pins.

In practice it was even worse. I was only able to use three of the four PWM pins on the Seeeduino Ethernet board. The board didn’t seem to have the performance to run the Ethernet connection and 4 PWM pins at the same time. Any three PWM pins, and network was fine. But adding the fourth would always result in unexpected behaviour. It would successfully run four PWM outputs while not using the Ethernet connection. But as soon as the connection kicked in? One of the PWM signals would wonk out.

No HTTPS

The last and biggest design downside of the Arduino Ethernet. No HTTPS. The Arduino Ethernet doesn’t have enough power to decrypt secured HTTPS connections. Pretty much the entire web runs HTTPS these days. So if you want to send or receive content over an encrypted link you are going to be out of luck. This was a major issue for my project (it receives data from a continuous integration server). I got around the problem by creating an intermediary server application. This server application strips the encryption from the link and dishes up the data I needed over regular HTTP. A dodgy work around till I replace the Arduino Ethernet with a Yún.

Overall

The Arduino Ethernet was an important precursor to the Yún. I also really liked how Seeed squeezed their board down by pushing the ethernet connector through the PCB. But with all the above limitations, I don’t think I will use an Arduino Ethernet (or derivative) again. I would much rather spring the extra bucks for the Yún. Seeed also make a derivative of the Yún, the Seeeduino Cloud. It only costs $5 more than a Seeeduino Ethernet (which is less than the FTDI breakout board you will need for the Ethernet). I give the Arduino Ethernet 0.5/5.

0.5 stars out of 5.