OctoPi-Zero Part 2


This is the hardware overview of building the octopi Zero.

The main problem with running a pi zero is lack of USB, and lack of networking. To solve this you need to get a USB HUB, powered USB hub preferably.

I have had allot of luck with this particular hub.

The pros of this HUB are the fact that Ethernet is built in. It works out the box on the raspberry pi using Raspiban Jessie distro. It also has a small receptacle to add power to it. I ended up desoldering the power receptacle and soldered on two wires instead.

For Wi-Fi I used a generic wifi chip made by Realtek. Just like anything realtek it was a royal pain to setup. Once setup however it works very well. This is the generic USB dongle I used. I used a generic dongle based on the Realtek 8188eu chip.
I had to upgrade my distro a few times to get this thing to run properly.

This is the configuration I used.
NOTE: there are two files that we are concerned with for Wi-Fi.


The Configuration should look like this.

ctrlinterface=DIR=/var/run/wpasupplicant GROUP=netdev

ssid="YourSSID" psk="YourPASSWORD" }


The configuration should look like this.

source-directory /etc/network/interfaces.d
iface lo inet loopback
iface eth0 inet dhcp

auto wlan0
allow-hotplug wlan0
iface wlan0 inet dhcp
wpa-conf /etc/wpasupplicant/wpasupplicant.conf
wireless-power off
iface default inet dhcp

Power and relay.

For power I used a buck converter based on the LM2596 buck converter. This converter should be able to supply 2-3A at 5v. This is enough for our needs.

The relay I used is also a fairly generic device. With that said not all relays will work with a pi. The ones that do work are often labeled for Arduino use. The one I had mentioned in my video does not trigger properly and has noise issues. This model is much better and works very reliably.

Safety warning.

Although these relays are marked for high voltage use. I would never connect this kind of relay to a high voltage source, nor would I trust it with anything close to 10A as market. I would not trust it with more than 1-2A at lower voltages. Be warned.

Relay wiring.

Simply put this relay is wired in parallel with a normal on off switch I have been using to trigger the psu to an ON state. The psu has the equivalent of a green to ground short to get it to power on.

Wiring Diagram.

Note my high-tech method of sharing a wiring diagram. Easy peasy. M$ Paint.

A case to stuff it all in.

This is the case I designed, I have uploaded it to youmagine. Download here. https://www.youmagine.com/designs/octopi-zero

Remember to post comments in youtube. I will ship one octopi-zero to one of my viewers.

Links to parts.

I wont include a raspberry pi zero in this as they are available from a variety of suppliers. (NOTE: I have no affiliation with the following suppliers, its just the most resonable cost I have come accross.)

Total = $23.88 providing you find a pi zero for ~$5.50

Bruno M.

Engineer, Tinkerer, Technologist, Maker.

New York

Subscribe to engineerd3d

Get the latest posts delivered right to your inbox.

or subscribe via RSS with Feedly!