Sun SPOT

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Sun SPOTs beside an AA battery

Sun SPOT (Sun Small Programmable Object Technology) was a sensor node for a wireless sensor network developed by Sun Microsystems announced in 2007. The device used the IEEE 802.15.4 standard for its networking, and unlike other available sensor nodes, used the Squawk Java Virtual Machine.

After the acquisition of Sun Microsystems by Oracle Corporation, the SunSPOT platform was supported but its forum was shut down in 2012.[1]

Hardware[edit]

The completely assembled device fit in the palm of a hand.

Its first processor board included an ARM architecture 32 bit CPU with ARM920T core running at 180 MHz. It had 512 KB RAM and 4 MB flash memory. A 2.4 GHz IEEE 802.15.4 radio had an integrated antenna and a USB interface was included.[2]

A sensor board included a three-axis accelerometer (with 2G and 6G range settings), temperature sensor, light sensor, 8 tri-color LEDs, analog and digital inputs, two momentary switches, and 4 high current output pins.[2]

The unit used a 3.7V rechargeable 750 mAh lithium-ion battery, had a 30 uA deep sleep mode, and battery management provided by software.[2]

Software[edit]

The device's use of Java device drivers is unusual since Java is generally hardware-independent. Sun SPOT uses a small Java ME Squawk which ran directly on the processor without an operating system. Both the Squawk VM and the Sun SPOT code are open source.[3] Standard Java development environments such as NetBeans can be used to create SunSPOT applications. The management and deployment of application are handled by ant scripts, which can be called from a development environment, command line, or the tool provided with the SPOT SDK, "solarium".[citation needed]

The nodes communicate using the IEEE 802.15.4 standard including the base-station approach to sensor networking. Protocols such as Zigbee can be built on 802.15.4. Sun Labs reported implementations of RSA and elliptic curve cryptography (ECC) optimized for small embedded devices.

Availability[edit]

Sun Microsystems Laboratories started research on sensor networks around 2004. After some initial experience using "Motes" from Crossbow Technology, a project began under Roger Meike to design an integrated hardware and software system.[4] Sun sponsored a project at the Art Center College of Design called Autonomous Light Air Vessels in 2005.[5] The first limited-production run of Sun SPOT development kits were released April 2, 2007, after months of delays. This introduction kit included two Sun SPOT demo sensor boards, a Sun SPOT base station, the software development tools, and a USB cable. The software was compatible with Windows XP, Mac OS X 10.4, and common Linux distributions. Some demonstration code was provided.[citation needed]

A developer from Sun gave a demonstration in September 2007.[2] After investigating commercial use, Sun moved to focus on educational users. The entire project, hardware, operating environment, Java virtual machine, drivers and applications, was available as open source in January 2008.[3][6][7]

Oracle Corporation acquired Sun Microsystems in 2010 and continued Sun SPOT development, through release 8 of the hardware (with Sun-Oracle logo) by March 2011.[8] The 2011 version included larger memories and a faster processor, but with fewer inputs.[9]

In 2012 the forum said it would be "down for maintenance" until "mid-June".[1] A new forum was started on the Oracle Technology Network on May 7, 2013.[10] David G. Simmons, one of the SunSPOT developers for Sun Microsystems, maintained a blog through the end of 2010.[11] He opened an alternative developers forum in July 2013 not connected to Oracle.[12]

References[edit]

  1. ^ a b "The SunSpotWorld Forums are down for maintenance". Oracle Labs. Archived from the original on June 9, 2012. Retrieved November 17, 2013. 
  2. ^ a b c d Simon Ritter (September 24, 2007). "Sun SPOTs In Action". Archived from the original on April 20, 2008. Retrieved November 17, 2013.  Republished in February 2011
  3. ^ a b "spots: SPOTs project". Archived from the original on 2008 through 2012. 
  4. ^ Rob Tow. "Sun "SPOT" Wireless Sensor Networks". Personal web page. Retrieved November 17, 2013. 
  5. ^ Jed Berk and Nikhil Mitter (2006). "Autonomous Light Air Vessels". Retrieved November 17, 2013. 
  6. ^ Austin Modine (January 29, 2008). "Sun open sources doohickeys: Tiny, sensor-driven devices exposed". The Register. Retrieved November 17, 2013. 
  7. ^ "Sun Brings Innovative Sun Small Programmable Object Technology (SPOT) Sensors to Open Source Community; Expands Program to Educational Institutions Around the Globe". Press release (Sun Microsystems). January 29, 2008. Archived from the original on February 3, 2008. Retrieved November 17, 2013. 
  8. ^ Ron Goldman (March 19, 2011). "Spots: Wiki: Home — Project Kenai". Project web site. Retrieved November 17, 2013. 
  9. ^ "SunSPOTWorld - Purchase". Commercial web site. Retrieved November 17, 2013. 
  10. ^ SunSPOT forum at Oracle Technology Network
  11. ^ "On the SPOT: David G. Simmons". Blog. Archived from the original on May 9, 2012. Retrieved November 17, 2013. 
  12. ^ "Sun SPOTs Forums". Alternative non-official developers forum. Retrieved November 17, 2013. 

External links[edit]