Thursday, July 17, 2014

Raspberry Pi Model B+ Review

CPC very kindly sent me a Raspberry Pi model B+ to try out.

As you can see, there are a few changes when you compare it to the Raspberry Pi Model B in the middle and the model A on the right. This board is a pretty serious upgrade to the Model B while still being very affordable at just £22.87 + VAT (about $40).

Raspberry Pi, models B+, B and A

The most obvious change is that there are now four USB ports rather than the two of the Model B. This is a great improvement and removes the need to have a USB hub connected to the Pi. It means you can have a keyboard, mouse, USB WiFi dongle connected and still have a spare slot for a USB pen drive.

I think that the provision of four USB ports is extremely significant, because it marks out the Raspberry Pi firmly as a real computer and not just another tiny Linux board designed to be used as an embedded controller.

This brings me on to another obvious change. The GPIO port has grown from 2 rows of 13 pins to 2 rows of 20 pins. Many people will never use the GPIO port on a Raspberry Pi, content to just use it as a computer. But if you want to use your Raspberry Pi to control electronics, you now have some more pins to do it with. The additional pins are at one end of the board to maintain compatibility with existing add-on boards.

Another change is the removal of the little-used composite video socket. This allowed you to attach AV monitors of the type used in CCTV to the Raspberry Pi. This connection is still available but supplied as an extra connection on the Audio jack, which is now an AV jack, combining both audio and video.

There are other changes, both cosmetic and improvements to the design.
  • The corners of the PCB are rounded off, which makes it look a bit sleeker and more professional. Not that that makes a blind bit of difference really.
  • Of more significance are new mounting holes arranged in a rectangle, rather than at random locations on the board.
  • The sockets aren't all in the same place (so you'll need a new case)
  • The power supply is now reverse polarity protected and the linear voltage regulators (which get hot) have been replaced by switching regulators (which don't).

Does it Work?
All in all, all these improvements are very welcome. I think that the Raspberry Pi foundation have hit the nail firmly on the head with this update. But of course the million dollar question for all of us who have model B boards is 'will our stuff work?'

Since I was using a full-sized SD card in my model B, I obviously could not just use the same SD card. Even if you are using a micro SD card in an adapter on a model B, you will still need to upgrade Raspbian to the latest version using a model B before moving the SD card over to to the B+. This is because the B+ uses a different Ethernet controller chip.

When setting up a Pi, I prefer to create a full Raspbian iso disk image using Pi Filler rather than use Noobs. This is because I generally use my Pi through SSH and VNC rather than attach keyboard, mouse and monitor. Noobs needs a keyboard mouse and monitor.

So, I created a micro SD card using the 2014-06-20 distribution of Raspbian. The Pi looked happy until I tried to ssh to it. No response. So, I plugged keyboard, mouse and monitor in, and rebooted. It did boot, but with a load of errors and then failed to run raspi-config.

Now that I had the Pi all accessorised, I thought I might as well try the latest Noobs and this worked perfectly, first time.

Lesson - if upgrading from a B, copy the stuff you need off to a flash drive, then run Noobs on a new micro SD card.

Next, I though I should try out the GPIO connector, so I put together the Charlieplex LED project from the Raspberry Pi Cookbook.

This all worked fine.

I also thought I had better check out the RasPiRobotBoard V2 and make sure that all was well with that. It was, so all in all no compatibility problems so far.

Next, I thought I had better test out I2C, so I plugged an Adafruit LED Backpack into the I2C socket of the RasPiRobotBoard, loaded up the Adafruit example code and everything worked just fine.

I didn't try out any of the new GPIO pins, but I have no reason to doubt them. You can find a pinout for them here. My next job is to update the Raspberry Leaf and make a B+ version.

I love this board. There's nothing wrong with the plain model B, but this positions the Raspberry Pi as the undisputed ruler of the Single Board Computer.

You may be interested in the books I have written about the Raspberry Pi.


David B. said...

I'll offer you my encouragement to proceed with your plans to make an RPi Leaf compatible with the new B+ RPi. The "Leafs" (Leaves?) are very handy, cheap and brilliantly simple. A suggestion: Can you make a PDF with multiple Leafs on one sheet of paper?

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beta devices