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Cluster of Raspberry Pi Zeroes

Posted by Mike Redrobe | Posted in Technology | Posted on 06-01-2016


No ethernet required – each pi zero is both powered and networked by a single usb lead !


The magic happens in the “gadget mode” firmware of the PI Zero. Since it doesn’t have the USB HUB chip in the way like other models (B / B+/pi2) it can be configured in device mode.

This makes it appear to any PC (or pi B+ / pi-2) as a virtual usb network adaptor – so you can immediately access it as though it were ethernet connected.
It also possible to set it up to appear as mass storage device, keyboard, mouse or any other usb peripheral!
(More discussion on the pi forums by DaveB and others)

Power isn’t a problem as each Pi Zero only uses around 150mA

    Convert a Pi Zero to gadget mode:

1. Start with an fresh image of Raspbian Jessie https://www.raspberrypi.org/downloads/raspbian/

2. copy this file to the boot partition: https://dl.dropboxusercontent.com/u/1122948/temp/PiOTG-Test/PiZeroEthernet.tar.gz (thanks to gbaman1 / Andrew Mulholland)

or download it on the pi itself:

wget https://dl.dropboxusercontent.com/u/1122948/temp/PiOTG-Test/PiZeroEthernet.tar.gz

2. sudo tar xvzfC /boot/PiZeroEthernet.tar.gz /tmp/

3. sudo cp -R /tmp/PiZeroEthernet/fat32/* /boot/

4. sudo cp -R /tmp/PiZeroEthernet/ext4/lib/* /lib/

5. Now give it a static ip address by editing /boot/cmdline.txt and adding this on the end: ip=

(for the lazy all the above has been done on this downloadable image:
http://sourceforge.net/projects/pizero-usbhost/ [768MB])

Now the pi Zero can be plugged into a pi2 / B+ (or a PC !) and you can SSH directly to it on the ip you set above (

[more to follow]

PiZero works with chromecast ethernet PSU

Posted by Mike Redrobe | Posted in Technology | Posted on 04-01-2016


Google sell a combined PSU and ethernet adaptor for the chromecast which works over a single micro usb….

Chromecast ethernet PSU

https://store.google.com/product/ethernet_adapter_for_chromecast [£15]

The PSU contains a USB-ethernet adaptor so it can provide both power and ethernet networking to the Pi Zero,which can be powered from the data usb port as seen above.

Power and networking with a single cable !

Fortunately the Pi Zero supports this chipset out of the box with Raspbian OS:

pi@pizero3:~ $ lsusb
Bus 001 Device 002: ID 0bda:8152 Realtek Semiconductor Corp.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
pi@pizero3:~ $ lsusb -t
/: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=dwc_otg/1p, 480M
|__ Port 1: Dev 2, If 0, Class=Vendor Specific Class, Driver=r8152, 480M

Speed ? Pretty good too:

pi@pizero3:~ $ iperf -c
Client connecting to, TCP port 5001
TCP window size: 43.8 KByte (default)
[ 3] local port 48478 connected with port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-10.0 sec 112 MBytes 94.2 Mbits/sec

Chromecast ethernet adaptor is £15 on google play:
https://store.google.com/product/ethernet_adapter_for_chromecast [£15]