The Raspberry Pi B+ Explored and Explained

Announced on 14th July 2014, the Raspberry Pi B+ is a revision to the hugely popular model B. Available at the same price as its predecessor, the B+ is the same but different. This tutorial will explain the differences and what's new with the model B+.

Originally launched in February 2012—and intended as an educational learning tool—the low-cost, bare-bones Raspberry Pi captured the imagination of kids (and big kids) around the world.  

History

For the kids of my generation, the Raspberry Pi is the spiritual successor to the BBC Model B microcomputer—a machine that brought real world computing to the classrooms of the 1980s.  

This makes sense, too, as the Raspberry Pi runs an ARM1176JZF-S CPU, or central processing unit. ARM being the Cambridge-based semiconductor designer that was founded by Acorn Computer, the firm behind the BBC Model B, and Apple Computer (now Apple Inc.)

Originally founded in November 1990 as Advanced RISC Machines Ltd, the company is now known as ARM. In the 1990s, ARM originally stood for Acorn RISC Machines and it was Acorn Computer that put the first ARM chips into the Acorn Archimedes computers.

The facts that the Raspberry Pi Foundation is based in Cambridge, as was Acorn Computer, they both produced computers with and educational bias and they both marketed their products as Model A and Model B, all serve to emphasise the spiritual link between Acorn Computer/Acorn RISC Machines (ARM) and the Raspberry Pi Foundation computers. 

Model B

Launched in February 2012, the Raspberry Pi was developed in the United Kingdom with the intention of promoting and teaching computing science in schools. 

This was a bold move, by founder Eben Upton, to move the emphasis away from schoolchildren being taught to use software packages, such as Word and Excel, rather than teaching them the concepts behind programming computers and learning how to make them useful rather than just how to use them.

Model B+

Two and a half years on and the Raspberry Pi Foundation is calling the B+ a “…hardware revision that incorporates a number of improvements…”, over the Pi model B. 

The Foundation states that the B+ “…is not Raspberry Pi 2, but rather the final evolution of the original Raspberry Pi."

Model B+ Improvements

USB Ports

The most obvious improvement, perhaps, is the addition of a further two USB 2.0 ports bringing the total to four. 

This makes much more sense as anyone who has wanting to plug in a Wi-Fi dongle and an external hard drive—in addition to the keyboard and mouse—will attest.

The Pi B+ also manages hotplugging and overcurrent behaviour, in the USB ports, in an improved manner over the model B.

Storage

The SD Card was always quite a large storage medium for the diminutive model B. The friction-fit was not the most positive experience, either.  

The new B+ uses an improved push-push MicroSD card that provides for both a more compact storage medium and a postive experience in inserting and removing the card.

As an added bonus, if you purchased a NOOBS card from the Raspberry Pi Foundation, this has been supplied as a MicroSD card inside and SD Card adapter. This gives you the best of both worlds in that it can be used for both models B and B+. 

When it comes to software, both models use the same, so you can still use Raspbian and NOOBS and all the other software that you used on the Model B.

Input / Output

A major change, on the B+, is the addition of 14 more GPIO pins to bring the total to 40 general purpose input/output connections.

The first 26 GPIO pins on the model B+ are the same as the 26 pins on the model B. This means that any projects for the B are compatible with the new model.

Audio

The quality of the audio is much improved. The audio circuit incorporates a dedicated low-noise power supply, ideal for plugging in either headphones or speakers.

Video

The Composite Video RCA, the yellow phono connector, on the model B has been removed from the B+. Video output is now via the HDMI port, as per the B, or via a four-pole AV (Audio Video) jack similar to the type used on many camcorders.

This might cause issues as not all of these four-pole AV plugs are the same configuration meaning that the left and right audio channels may become reversed.

Power

Lower power consumption. By replacing linear regulators with switching ones the Raspberry Pi Foundation has reduced power consumption, of the model B+, by between 0.5W and 1W. 

This is good news if the Pi is powered by batteries, such as in a robot.

Form Factor

The model B+ has a neater form factor. They’ve aligned the USB connectors with edge of the board. The composite video has been moved onto the 3.5mm jack, and the device uses a smaller SD Card.

The addition of four squarely-placed mounting holes is a neat touch that allows the secure fixing of the B+ into specific projects, onto the wall and into cases, perhaps.

Cases

Due to the slightly different physical design, existing model B cases will not work with the B+.

Cost

This isn’t a difference. The Raspberry Pi model B+ is offered at exactly the same price as the model B. The model B is still in production alongside the model B+.

Specification Comparison

Conclusion

The model B+ is, in the words of the Raspberry Pi Foundation “…a hardware revision that incorporates a number of improvements…” over the immensely successful model B

Given that the model B+ is the same price as the model B, it’s really up to you which you think is the best purchase for your particular project. If it’s just for learning, the model B+ is the sensible device to purchase.