Awaiting for the new release, Arduino Yun, I think it's very interesting to know more about the new linux devices in the market. There are a lot of emerging ones and many of them agree in the same feature: to be Arduino-compatible.
Arduino was launched in 2005 and it has become in a standard as a modular platform, so all new devices want to add this feature, allowing people to use each platform as easy as Arduino.
Some can carry Ethernet, Wifi, HDMI, NAND flash... these features change in each board we are going to compare. But all of them have GPIOs, and even an expansion board to make the port easy.
A quick review of each one
|Arduino Yun. Arduino Yún is the combination of a classic Arduino Leonardo (based on the Atmega32U4 processor) with a Wifi system-on-a-chip running Linino (a MIPS GNU/Linux based on OpenWRT). It’s based on the ATMega32u4 microcontroller and on the Atheros AR9331, a system on a chip running Linino, a customized version of OpenWRT, the most used Linux distribution for embedded devices. Like a Leonardo, it has 14 digital input/output pins (of which 7 can be used as PWM outputs and 12 as analog inputs), a 16 MHz crystal oscillator and a micro USB connector.
|BeagleBoard-xM. BeagleBoard-xM delivers extra ARM ® Cortex TM -A8 MHz now at 1 GHz and extra memory with 512MB of low-power DDR RAM, enabling hobbyists, innovators and engineers to go beyond their current imagination and be inspired by the BeagleBoard.org community. Designed with the community inputs in mind, this open hardware design improves upon the laptop-like performance and expandability, while keeping at hand-held power levels. Direct connectivity is supported by the on-board four-port hub with 10/100 Ethernet, while maintaining a tiny 3.25" × 3.25" footprint.|
|BeagleBone A6. BeagleBone is a credit-card-sized Linux computer that connects to the Internet and runs software such as Android 4.0 and Ubuntu. With plenty of I/O and processing power for real-time analysis provided by an AM335x 720MHz ARM® processor, BeagleBone can be complemented with cape plug-in boards to augment functionality.|
|Cubieboard. Cubieboard is a small (10x6cm), hacker friendly, extendable and very low-cost while powerful ARM board with Allwinner A10 SoC.|
|pcDuino. pcDuino is a mini PC platform that runs PC like OS such as Ubuntu and Android ICS. It outputs screen to HDMI. Moreover, it has hardware headers interface compatible with Arduino.|
|RascalMicro. The Rascal is a small computer that you can use to monitor and control the world remotely. The Rascal is powerful enough to handle real web traffic, but you don't have to be a professional electrical engineer to use one. The Rascal has its own web-based editor on board, it works with most Arduino shields, and you can program it in Python.|
|Raspberry Pi. The Raspberry Pi is a credit-card sized computer that plugs into your TV and a keyboard. It’s a capable little PC which can be used for many of the things that your desktop PC does, like spreadsheets, word-processing and games. It also plays high-definition video. We want to see it being used by kids all over the world to learn programming.|
Which one should I choose?
As I said in my previous post, comparing Arduino Yun and Raspberry Pi, it depends of your final purpose:
miniPC: if you are looking for a portable PC with HDMI connection, there are 4 options in the table: BeagleBoard-xM, Cubieboard, pcDuino and Raspberry Pi, but Raspberry Pi allows to use a RCA output if your TV doesn't support HDMI connection. You can run a Linux distro, but you will need more RAM, depending of the use of your computer. In this case, you can choose between 1Gb (Cubieboard, pcDuino) or 512Mb (Raspberry Pi, BeagleBoard-xM). Regarding to the storage, Cubieboard has 4Gb NAND flash so you can take advantage of this feature instead of using an external storage. BeagleBoard-xM would be the most complete among them, with more I/O connectors for A/V: camera, S-Video, Audio (play, record)... Raspberry Pi and Rascal Micro would be the next but, if the price is one of the most valuable variables, Raspberry Pi would win.
Arduino compatible: if you are looking for a direct Arduino compatible device, there are 5 options. The first one, Arduino Yun. It is the only one with embedded WiFi connection. It has a MIPS-based Wi-Fi SoC running Linino (similar to OpenWRT) so you can control the web server with this device and use it as a common Arduino (with the Digital/Analog I/Os). Rascal Micro and pcDuino have the same Arduino sockets so you will be able to plug any Arduino shield directly. There are some expansion shields or bridges for the other platforms, like the Raspberry Pi to Arduino Shields Connection Bridge. In this case, I'd choose Arduino Yun. Nice device which derives the complex control of WiFi connection through a Linux distro and combines it with the easy programming of the common GPIOs.
Here you can find a comparison between the boards:
|Name||Arduino Yun||BeagleBoard-xM||BeagleBone A6||Cubieboard||pcDuino||Rascal Micro||Raspberry Pi Model B|
|Processor||ATMega32u4 16 MHz||ARM Cortex-A8 1 GHz||TI AM3359 ARM Cortex-A8 720 MHz||Allwinner 1 GHz ARM Cortex-A8||1 GHz ARM Cortex A8 CPU||AT91SAM9G20 ARM926EJ/S @ 400 MHz||BCM2835 ARM11 700 MHz|
|Graphics||N/A||C64x, DSP core||LCD||Mali-400||OpenGL ES2.0, OpenVG 1.1 Mali 400 core||N/A||Broadcom VideoCore IV|
|RAM||2.5KB||512 MB LPDDR||256 MB DDR2||512M/1GB DDR3 @ 480 MHz||1 GB DRAM||64 MB||512 MB|
|Storage||32 KB flash||4 GB flash (microSD)||4 GB flash (microSD)||4 GB NAND flash||2GB Flash||microSD card||SD Card|
|Size||2.7” x 2.1”||3.25” × 3.25”||3.4” × 2.1”||3.94” x 2.4”||4.93” x 2.05”||2” x 4”||3.37” × 2.125”|
|Input Voltage||5V||5V||5 V||5V||5V||5 V||5 V|
|Interfaces||Digital GPIO 14||RS232, I2Cm I2S, SPI, GPIO||GPIO I2C UART SPI CAN||I2C, SPI, IR||Digital GPIO 14||Digital GPIO 14||GPIO, UART, I²C, SPI|
|USB 2.0||microUSB, USB||Yes (4)||Yes||Yes (2)||microUSB, USB||Yes (2)||Yes|
|USB Device||USB Host||Client, Host||Client,Host||Host||Client,Host||USB Host||USB Host|
|Wi-Fi||Yes, Atheros AR9331 MIPS-based Wi-Fi SoC running Linino,||No||No||No||No||No||No|
|Audio Out||No||Yes||No||Yes||No||Pins for I2S||Yes|
|Analog Out||7 (PWM)||Yes||8 (PWM)||Yes||6 (PWM)||7 (PWM)||Yes|
|Other Video Out||No||Camera, SVIDEO||No||No||No||No||RCA|
Cooking Hacks Team