The similarities between the original BCM2835 and the new quad-core BCM2 extend to their support for overclocking, providing power users with a means to squeeze a little more power out of their Raspberry Pi the risk of a shortened lifespan. The safest way to get some extra speed out of your new device, assuming you’re running Raspbian, is to use the configuration wizard. At the terminal, type:
sudo raspi-config
Scroll down to 7 Overclock, hit Enter, read and acknowledge the warning, then choose the bottom option – labeled Pi2 – from the list that appears. Make sure you don’t use any of the other options, including None; these settings are designed for the original Raspberry Pi, and could leave your shiny new Pi 2 running slower than stock speed. Exit the tool by tabbing to Finish and confirm you’d like to reboot when asked. For even higher speeds, you can adjust settings directly within the boot configuration file. Run the following command at the terminal:
nano /boot/config.txt
Head to the bottom of the file, and use the following to adjust the performance of the processor:
arm_freq - Core clock frequency in megahertz
gpu_freq - GPU clock frequency in megahertz
sdram_freq - Memory clock frequency in megahertz
over_voltage - Increase the SoC’s voltage, in steps of 0.025V
Be aware, however, that manually adjusting these settings – in particular the voltage – can render your warranty void.
GPIO expansion
Although the latest Raspberry Pi models have a longer general-purpose-input-output (GPIO) header than their predecessors, it still lacks many functions of rival devices – in particular support for hardware pulse-width modulation (PWM) or analogue inputs. The solution is a GPIO expansion board.
There are plenty of add-ons from which to choose, many of which are tailored to a particular task such as robotics or home automation. A comprehensive list is available at [elinux.org/RPi_ Expansion_Boards].
Updating the firmware and kernel
You’re almost certainly aware that Raspbian needs regular updates to keep it performing in tip-top condition, but you may be running an older kernel and firmware release if you’re relying on the traditional method of using this command:
sudo apt-get update && sudo apt-get upgrade
To ensure you have the very latest kernel and modules – providing bug fixes, stability and even performance improvements – you need to use a separate tool bundled with Raspbian. At the terminal, type the following command:
sudo rpi-update
This command refreshes the firmware, kernel and all the modules from the official GitHub repository, ensuring that your system is bang up to date.
Multi-boot via NOOBS
While its name may suggest that it’s designed for newcomers, NOOBS (New Out-Of-Box Software) includes one feature that power users may find very useful indeed: multi-boot support. Download NOOBS from [www.raspberrypi.org/downloads], and extract the contents of the Zip to a FAT32-formatted micro-SD card – there’s no need to mess around flashing raw images. Insert the card into the Pi and boot it, then tick the boxes next to as many operating systems as you’d like to install.
When installation is complete, the next boot will load a menu asking which of the installed operating systems you want to boot. Future boots will display this menu for ten seconds, after which the most recently booted OS will be automatically selected. When installing your OS, however, be aware that not every choice available in NOOBS is yet compatible with the Raspberry Pi 2.
