A couple of posts back, I presented a quick comparison between the Raspberry-Pi Model B and the Arduino Mega2560, which seemed like a good idea at the time, given their similar price-points. Little did I know there was a third contender in the up-and-coming world of powerful prototyping boards, or hobby-oriented embedded systems (whatever the official name is for this new market), Beagleboard’s own Beaglebone.
Background and motivation
Beagleboard is closely affiliated to Texas Instruments, to the point that they state in their own website that some of the active members of the organization are TI-employees. This is probably a good thing given the fact that a lot of the ICs used in the Beaglebone come from TI, including the SoC, regulators, USB and ethernet PHY-chips, etc. It also means that whatever the customer is getting as architecture, it’s “close to the source.” Their motivation is to create “powerful, open, and embedded devices.”
The Raspberry Pi foundation is a non-profit based out of the UK. Its goal with the Raspberry Pi is to promote hands-on experience with computing systems that are easy to work with, kind of how kids used to play with QBASIC back in the late 80′s.
Ok, now the good stuff. By default, the BeagleBone carries a bigger SoC, so it should be more powerful… but what about all the other stuff that comes around with it?
|Raspberry Pi Model B||BeagleBone||Winner|
|Processor||Broadcom ARM11 @ 700 MHz||TI ARM Cortex A8 @ 720 MHz||BeagleBone|
|Processor Architecture||32-bit ARM v.6||32-bit ARM v.7||BeagleBone|
|GPU||Broadcom videocore, capable of OpenGL, OpenVG, Full HD||TI videocore with 3D-graphics accelerator||?|
|RAM||512 MB DDR2||256 MB DDR2||Raspberry|
|Storage||SD (not included)||microSD (4GB card included)||BeagleBone|
|Storage Size||Expandable through USB||Expandable through USB||Tie|
|USB||2 ports||2 ports||Tie|
|Ethernet||1 port, 10/100 Mbps||1 port, 10/100 Mbps||Tie|
|Video Output||Composite or HDMI||24-bit LCD controller with touch-sensing driver||Raspberry|
|PWM||Audio Jack||8 channels||BeagleBone|
|ADC input||No||7 channels, max input = 1.8V||BeagleBone|
|CAN||No||2 channels without PHY||BeagleBone|
|Power consumption||3.5 W||~ 3.5 W||Tie|
|Size||85.60 mm x 53.98 mm||86.36 mm x 53.34 mm||Tie|
|OS||Linux-based, Qt-based||Linux-based, Android, [edit: Other non-Linux OSes supported]||Tie|
|Expansions||Standard USB accessories as supported by Linux||Standard USB accessories as supported by Linux, expansion through headers||BeagleBone|
Now, this table is interesting. Take the “size” variable, for example. There’s no doubt that even though these are two entirely different crowds, they had the same idea in mind. Execution is slightly different though; the BeagleBone board is closer to a developer board, with two rows of headers on its sides, while the Raspberry only offers a limited number of pins for breadboarding.
The Raspberry Pi’s strongest point continues to be its full-HD HDMI output, but the BeagleBone offers out-the-box touch-sensing. The Raspberry Pi foundation also recently announced an upgrade from 256 to 512 MB in RAM for all of their in-production Rev. B. boards, for the same price. Needless to say, this has been well received by the community. In all justice, BeagleBoard did something similar for another one of their boards.
Development & Prototyping
Although the BeagleBone is, without a doubt, a superior number-cruncher, and a superior control-device with more SPIs, I2Cs, ADCs, timers, and UARTs, one must say that the Raspberry Pi holds surprisingly well given the price differences. Again, I can get a Raspberry Pi with a power-supply, no HDMI cable, no SD card for ~34€. Add both, and total price is still under 50€. A BeagleBone is US$89 (or about 74€, for those that like comparing apples to apples), but it already includes a power supply and a microSD card. Roughly speaking, the Raspberry Pi is 2/3 the price of the BeagleBone.
Very similar between them, for 25€ more gets you a ton of low-level interfaces, a touch-screen interface, but you lose full out-of-the-box HD-support. As with everything-engineering, you need to choose your weapon according to your project.
With the rise of smartphones and tablets, it seems too that there’s been an increased focus on bigger, faster, better embedded microcontrollers. This, in turn, has brought attention to porting “real” OSs into these systems, and voila!, now we’ve got a number of competing prototyping solutions with real computing power. But the embedded programers profession has been changed forever. Programs compiled through gcc, java applications, & bash scripts will transform traditional apps jobs into something much closer to IT server management. Yes, there will still always be need for someone to port kernels into specific devices, and there will always be need for someone to write boot code, but as long as Moore’s law stays a law, and as long as power consumption continues to decrease with new iterations of silicon, the future of embedded systems development looks much more like Linux and much less like electronics engineering.