Mar 01

Raspberry Pi 3 is out!

We are excited about the new Raspberry Pi 3 that was just released. Its use of a more powerful ARM Cortex A53 processor, Wifi and Bluetooth will make it even easier to build systems. Some have been ordered already for coursework!

Raspberry Pi 3

The processor even uses Big.LITTLE technology from ARM. This is now used on some phones/tablets as it means a lower power consumption overall. It does this by pairing each core with a smaller less power hungry core and using them when full performance is not needed.

Permanent link to this article: http://blog.soton.ac.uk/pi/2016/03/01/raspberry-pi-3-is-out/

Mar 29

Parallel Image Processing test on the new Raspberry Pi 2

Now there are four cores – and better ones – I felt the need to run our VIPS benchmarks to see how well the cores can work together. ┬áThis is CPU-bound so is not affected by the micro-SD card speeds. Here are my results using vips-7.42.3:

Threads, time(s), speed-up

1, 92, 1

2, 48.2, 1.9 x

3, 32.5, 2.8 x

4, 23.2, 3.96 x

 

I ran them in console mode so there were no desktop threads running (although the little CPU meter is interesting if you do that – showing 25% 50% 75% 100% roughly as you increase the cores used.

Conclusion: the Pi2 is about a quarter of the speed of an old core-2 duo type core and certainly slower than the ARM A15 found in modern tablets/chromebooks. Parallel processing on the Pi does work well however with a 4 core speed-up of 3.96 times.

Kirk

Permanent link to this article: http://blog.soton.ac.uk/pi/2015/03/29/parallel-image-processing-test-on-the-new-raspberry-pi-2/

Nov 27

Wires!

People soon need some wires – especially to plug into a little breadboard. These ones from ModMyPi are handy. For socket-socket these from Hobbytronics are also good.

Permanent link to this article: http://blog.soton.ac.uk/pi/2013/11/27/wires/

Nov 19

Eduroam WiFi on the RPi

This is how I configured a Pi to use Eduroam. Note that this is quite old and may be site specific sorry!

 

in the WIFI Config ap Scan to find Eduroam

Edit its config and check you have:

WPA2-Enterprise (EAP)

Encryption: CCMP

EAP Method: TTLS

identity: yourID@soton.ac.uk

Password: your university password

CA certificate: /etc/ssl/certs/AddTrust_External_Root.pem

Inner auth: MSCHAPv2

Permanent link to this article: http://blog.soton.ac.uk/pi/2013/11/19/eduroam-wifi-on-the-rpi/