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Gertboard Raspberry Pi add-on launches

Gertboard Raspberry Pi add-on launches

The Gertboard expands the capabilities of the Raspberry Pi's GPIO port - but it doesn't come cheap.

The Gertboard add-on for the Raspberry Pi microcomputer has been officially launched, with distributor Farnell advising of a two-month lead time for a kit-form version.

Designed by Broadcom engineer Gert van Loo, the Gertboard is designed to connect to the Raspberry Pi's general purpose input-output (GPIO) header in order to provide significantly improved functionality including analogue-to-digital conversion and motor control with no additional parts required.

Previously available only in limited numbers as a prototype, van Loo has revised the design of the board extensively in order to improve its functionality. In its finished form, the board includes buttons and LEDs for instant feedback and control, analogue-to-digital and digital-to-analogue converters for more complex projects and an in-built H-bridge motor controller.

If that little array of accessories wasn't enough, van Loo's updated design includes an integrated Atmel microcontroller - the same chip which sits at the heart of the Arduino board. Programmable directly from the Pi's GPIO port using the Atmel AVR software development kit (SDK,) the chip gives the Pi real-time sensing and control capabilities missing from the original design.

The chief design ethos for the Gertboard, van Loo explains, was to create a device designed explicitly for learning how to control input and output devices. 'The first step is to deal with the I/O directly, read a button or drive an LED. The second step is to deal with the I/O indirectly where you talks to a block which then talks to the outside. The third step in handling I/O is to talk to a processor which talks to a block which talks to the outside world,' van Loo explains of his methodology. 'That is where the ATmega comes in. As you can see, the board is not an arbitrary bundle of electronics but has been designed with a clear teaching path.'

Provided in kit form - teaching the essential skill of soldering as an added bonus - the Gertboard includes all the necessary components, a cable for connecting the board to the Pi's GPIO header, 20 example programs and a digital 43-page manual.

Sadly, the complexity of the Gertboard does come at a price: Farnell are currently taking pre-orders for £36 including VAT, making the add-on board around £6 more expensive than the Pi itself.

More information, including international ordering details, are available on the element14 site - but be warned: the Gertboard has already taken enough orders to extend the lead time from the original few weeks to a full two months.

6 Comments

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BLC 9th August 2012, 13:23 Quote
Yikes. That's a hell of a lead time... But I guess it pales in comparison to the Raspberry Pi lead times if you weren't one of the lucky recipients of the first batch (thankfully, I was!)

It's quite an expensive add-on, but it's comparable in price to an Arduino Mega (although slightly more expensive than the Uno). I don't know how well the number of IO pins stacks up against the Mega, but this seems to be a more flexible device when paired with a Pi - you certainly don't get an in-built H-bridge on the Mega.

More importantly however, the combined cost for a Pi and a Gertboard is a very attractive one indeed - especially for educational purposes. If we had something like this when I was in school then we wouldn't have needed the Lego robotics kits that we only got to use twice in two years.
Mraedis 9th August 2012, 13:24 Quote
I would love some of these boards, if only I knew what to do with them. ^^
Gareth Halfacree 9th August 2012, 13:44 Quote
Quote:
Originally Posted by BLC
It's quite an expensive add-on, but it's comparable in price to an Arduino Mega (although slightly more expensive than the Uno). I don't know how well the number of IO pins stacks up against the Mega, but this seems to be a more flexible device when paired with a Pi - you certainly don't get an in-built H-bridge on the Mega.
It's significantly more expensive than the Leonardo, however: £36 to around £19. Sure, you get an H-bridge - £3.50 - and some buttons and LEDs - £2.50 and £3.50 - but it's still an add-on device which costs more than the Pi itself.

By contrast, you could buy a Slice of Pi for £3.90 along with the Leonardo - which does things the Gertboard can't do, like pretend to be a keyboard, mouse or joystick input and work with the easy-to-learn Arduino IDE - and the aforementioned accessories for £32.40. If you don't need the Arduino, that cost drops to £13.40 - and you can always add in a standalone ATmega microcontroller for about £4.

Don't get me wrong, I think the Gertboard is great - but I'd like to see a version made with fewer discrete components and at a significantly reduced cost. If the Gertboard was £15, it'd be a no-brainer.
goldstar0011 9th August 2012, 13:46 Quote
Quote:
Originally Posted by Mraedis
I would love some of these boards, if only I knew what to do with them. ^^

My thoughts exactly, I bought the Pi for some reason but don't actually need so sold it, will get one later down the line
BLC 9th August 2012, 15:21 Quote
Quote:
Originally Posted by Gareth Halfacree
It's significantly more expensive than the Leonardo, however: £36 to around £19. Sure, you get an H-bridge - £3.50 - and some buttons and LEDs - £2.50 and £3.50 - but it's still an add-on device which costs more than the Pi itself.

By contrast, you could buy a Slice of Pi for £3.90 along with the Leonardo - which does things the Gertboard can't do, like pretend to be a keyboard, mouse or joystick input and work with the easy-to-learn Arduino IDE - and the aforementioned accessories for £32.40. If you don't need the Arduino, that cost drops to £13.40 - and you can always add in a standalone ATmega microcontroller for about £4.

Don't get me wrong, I think the Gertboard is great - but I'd like to see a version made with fewer discrete components and at a significantly reduced cost. If the Gertboard was £15, it'd be a no-brainer.

I have to confess that it's been a while since I shopped around for Arduino boards; I'd never heard of the Leonardo before now...

Where I can see the utility in the Gertboard is in educational use; it's more or less a complete package for getting started in robotics and interfacing with the "outside" world. No need to try and source the individual components on their own, because it's all in one package from one supplier. Of course it doesn't have actuators, servos, etc, but doubtless there are already plenty of starter kits for that stuff. I don't know if plans are still in the pipes for this, but I know initially the foundation planned to have an "educational release" for the Raspberry Pi; this was due to be when the Model A launched, along with a range of cheap accessories, supporting documentation and more stable/mature software. If such a plan is still on the cards, the Gertboard could easily form part of it.

To be perfectly frank, I'm really not interested in the Gertboard at all. I agree that it is expensive, but I don't really think it's aimed at people like me. Not to say that there is no utility in it for me at all, but I'd be quite happy with working out how to programatically use the GPIO pins and writing my own code to make use of them. If I needed to, I could probably have a crack at building my own GPIO interface board.

Plus I already have an Arduino Duemilanove, which works with the Pi. The Arduino IDE might not work on the Pi, but my laptop will do for now - I'll jump off that bridge when I come to it!
Necrow 9th August 2012, 15:33 Quote
I bought a Pi with the intention of adding it into my 4x4 for monitoring temperatures and pressures, so far I took it out of the box once and put it back again lol

I don't have enough time to fully research this project but this board looks like it may help me with converting some of my Temp signals to Alarms etc....
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