The Original BeagleBone versus the BeagleBone Black

By Rui Santos, Luis Miguel Costa Perestrelo

When you first get your BeagleBone, you’ll find the board and a Mini USB cable inside the box. If you purchased an Original BeagleBone, you also get a 4GB microSD card. That’s everything you need to get started, along with your computer.

There are two distinct versions of the BeagleBone: the Original BeagleBone and the BeagleBone Black. The two boards are similar except for a few small details. Here is the Original BeagleBone:

[Credit: Photo courtesy of Adafruit Industries]

Credit: Photo courtesy of Adafruit Industries

Another familiar, common designation on the web for the BeagleBone Black is BBB. Here is the BeagleBone Black:

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At a first glance, you may feel intimidated about grabbing such bare boards. They are so tiny and seemingly fragile, yet so powerful. Certainly, you’re curious to understand all the tiny components sitting on top of your BeagleBone.

Following are the components featured in both the Original BeagleBone and the BeagleBone Black:

  • Processor: You can call the processor the “brains” of your BeagleBone. Both boards feature an ARM Cortex-A8 operating at a maximum speed of 720MHz for the Original BeagleBone and 1GHz for the BeagleBone Black. This means that the latter makes a decision/calculation every 0.000000001 second!

  • RAM: The Original BeagleBone has 256MB of DDR2 (Double Data Rate 2), whereas the BeagleBone Black has 512MB of DDR3.

  • microSD card slot: The Original BeagleBone doesn’t have any built-in memory, so it always needs to have a microSD card inside to be able to work. By default, it comes with a 4GB microSD card. The BeagleBone Black doesn’t come with a microSD card because it has built-in memory. Regardless, you can still insert a microSD card into it to install or update your operating system or because you want to have more available memory to play around with.

  • DC power connector: Your BeagleBone needs 5 volts (V) and 500 milliamps (mA) of direct current to power up.

    Connecting the BeagleBone to your computer with a USB cable also provides the necessary power for the board to power up.

    If you have a connector that fits into your BeagleBone connector, that doesn’t necessarily mean that it’s the right power adapter! Not all power adapters provide exactly 5V; some of them actually provide 12V. You also need to check for the connector’s polarity; the center ring has to provide the 5V and the outer ring has to provide Ground (GND). You need to be careful. Even though the board has a voltage regulator, feeding it excess power or wrong polarity could permanently damage it!

  • USB client: Both boards offer an USB client for powering up, communications, and debugging.

  • USB host: Both boards include one USB port. This port enables you to connect peripherals such as a keyboard or a USB stick.

  • Ethernet: Both boards feature a standard RJ45 Ethernet port. By plugging an Ethernet cable in it and connecting the BeagleBone directly to a router or by sharing the Wi-Fi connection of your computer, you can easily manage software on your BeagleBone, as well as build projects that require an Internet connection.

  • Headers: The BeagleBone headers, labeled P8 and P9, can be used in many ways. You can use them to insert capes or supply power, for example, and you can program them to establish communications with other devices or act as inputs or outputs.

  • USR LEDs: The USR LEDs indicate the status of your board:

    • USR0: Blinks for as long as the system is running

    • USR1: Blinks whenever the microSD card is being accessed

    • USR2: Blinks to indicate that the central processing unit (CPU) is active

    • USR3: For the BeagleBone Black, this LED blinks when the eMMC (embedded MultiMediaCard) memory is being accessed

  • Reset button: This button resets your board when you press it. Keep in mind, though, that your BeagleBone is just like a regular computer; you should reboot it this way only when it crashes.

Besides the previously mentioned components, the BeagleBone Black has a few additional components. These are:

  • eMMC: The eMMC memory is the built-in memory on your BeagleBone Black. The amount you have depends on your BeagleBone Black’s revisions (Rev):

    • BeagleBone Black Rev A and B: 2GB of eMMC memory

    • BeagleBone Black Rev C: 4GB of eMMC memory

  • Micro HDMI: This port is used to connect your BeagleBone Black to a computer display or a television set.

  • Serial header: The BeagleBone Black has a separate header for one of its serial ports, enabling you to easily connect a USB-to-TTL serial cable (read Chapter 3 for more on this topic).

  • Power button: If you press the power button, the board shuts down after a few seconds. You can turn it ON once more by pressing the power button again. You can also do a full power cycle by pressing the board for about 10 seconds; the board turns OFF and then comes back ON. You should avoid this, though, as it may corrupt the eMMC or SD card. Use it only if your board is not responding to your commands.

  • User boot button: By default, your BeagleBone Black boots from onboard memory with the operating system (OS) installed there. By holding down this button when you power the board, you indicate that you want it to boot from the microSD card. You also use this button to install an operating system on the eMMC.