PiJack: Add Ethernet to Raspberry Pi Zero!
PiJack: Add Ethernet to Raspberry Pi Zero!
PiJack is a simple "shield" board which adds 10Mbps ethernet conenction to Raspberry Pi Zero in the most convenient way possible.
PiJack is a simple "shield" board which adds 10Mbps ethernet conenction to Raspberry Pi Zero in the most convenient way possible. Read more
Raspberry Pi Zero is a new board from Raspberry Pi Foundation which retails for $5. This is a fully functional Linux system - similar to Raspberry Pi 2 and although it lacks many ports we can live without, we can't live without without Internet access.
PiJack is an add-on board you plug on top of your Raspberry Pi Zero which adds Ethernet functionality to your $5 system, therefore you can use the traditional Ethernet / Internet cable to connect your RPI Zero to the network (Internet).
We aimed for low-cost solution and ease of installation and therefore went for trusty ENC28J60 ethernet chip, which is only 10Mbps, but super simple to install and to use with Raspbian. The only thing that needs to be done is add one config line into one file on SD card your Pi boots from. And thats it. With Raspbian Lite version you get internet using DHPC on the next boot. Automagically.
We have completely designed the board ourselves - some of the main design decisions were:
- well-know ethernet chip used in many Arduino and IoT projects
- is super easy to install and supported by Raspbian
- same board footprint and thickness as Raspberry Pi Zero board
- has board cutouts for two RPI Zero mounting holes for ease of installation in boxes and enclosures
- has minimum parts -> simpler assembly -> cheaper
- has a proper regulated power supply from RPI's 5V output (which 99% of ENC28J60 boards don't have!) protecting RPI's 3.3V circuit from overloading
- is completely designed in open-source KiCad EDA (which is amazing!)
- has ethernet jack with two status LEDs (more expensive, but more user friendly)
PiJack is based on 10Mbps ENC28J60 ethernet chip powered from Raspberry Pi's 5V DC output available via GPIO pins, then 3v3 transformer is used to power the ethernet circuit. Ethernet jack - RJ45 - has two LEDs - one to indicate link UP and the other to indicate activity on the line. Jack has a built-in magnetic transformers integrated in its housing.
Heat dissipation analysis
While going though datasheet of the Ethernet chip used in PiJack and digging into internals of the chip we could see many metions in discussions on the internet of the chip getting quite hot - so we made some measurements. The max temperature we could measure is 66 degrees celsius (around 150F), which is still okay, but feels quite warm. This is normal for this chip, but please bare this in mind when using the module in environments sensitive to heat.
We are in talks with production house based in Slovakia - part of an EU - mostly because we have a detached office based in Bratislava, but also because this is a big, local company producing electronics for automotive industry (Slovakia is the world's number one auto maker per capita). We aim to produce, assembly and quality-test the boards on one place. Most of the parts are sourced locally - meaning European Union.
Installation and documentation
Installation and documentation on how to use PiJack will be available on our homepage pijack.net before we ship the first units out. Its really simple - you may want to rewatch our KS video to see how straightforward this really is.
Authors and thanks
PiJack was designed by Marcel Hecko and Al Bennet of Hot Glue Technologies, Edinburgh. Thanks for inspiration to RaspiTV and Raspberry Pi Foundation. Thanks for helping with the video goes to Monca. Music track in the video: "Telluric Undercurrent" by Revolution Void (http://www.revolutionvoid.com)
Risks and challenges
Its It might not seem so, but designing electronics out of Asia is actually pretty difficult - mostly because of the lead times and prices of electronic parts everywhere else out of Asia. Electronic parts are expensive and therefore the PiJack seems rather more expensive than expected. This is mostly because of the import taxes and duties that we have to include on top of the price of the products imported from outside of EU in addition to high price of other components sourced in Europe - and higher cost of assembly.
We are aware of this and very careful not to run out of money before delivering the product. We are being absolutely realistic about the pricing.
Another challenge is the classification of the product - please mind, that PiJack is (at this stage) offered as a development platform, which is categorised differently to traditional electronics you can buy for home or industrial use.
One more risk that deserves mentioning is the support of ENC28J60 chip with Raspbian OS - we will work with Raspbian community to keep the chip supported in the future - this really is a chicken-and-egg problem - if we get the PiJack funded, we will definitely have more means to keep the chip supported in the future.
- (30 days)