Nano-RK
Encyclopedia
Nano-RK is a real-time operating system
(RTOS) from Carnegie Mellon University
designed to run on micro-controllers for use in sensor networks. Nano-RK supports a fixed-priority fully preemptive scheduler
with fine-grained timing primitives to support real-time task sets. "Nano" implies that the RTOS is small consuming 2K of RAM
and using 18K of flash
, while "RK" is short for Resource Kernel. A resource kernel provides reservations on how often system resources can be consumed. For example, a task
might only be allowed to execute 10ms every 150ms (CPU Reservation), or a node
might only be allowed to transmit 10 network packets per minute (Network Reservation). These reservations form a virtual energy budget
to ensure a node meets its designed battery lifetime as well as protects a failed node from generating excessive network traffic. Nano-RK is open source
, written in C
and runs on the Atmel
based FireFly sensor networking platform, the MicaZ motes as well as the MSP430 processor.
The following article discusses some of the tradeoffs associated with using an RTOS in sensor networks.
Real-time operating system
A real-time operating system is an operating system intended to serve real-time application requests.A key characteristic of a RTOS is the level of its consistency concerning the amount of time it takes to accept and complete an application's task; the variability is jitter...
(RTOS) from Carnegie Mellon University
Carnegie Mellon University
Carnegie Mellon University is a private research university in Pittsburgh, Pennsylvania, United States....
designed to run on micro-controllers for use in sensor networks. Nano-RK supports a fixed-priority fully preemptive scheduler
Preemption (computing)
In computing, preemption is the act of temporarily interrupting a task being carried out by a computer system, without requiring its cooperation, and with the intention of resuming the task at a later time. Such a change is known as a context switch...
with fine-grained timing primitives to support real-time task sets. "Nano" implies that the RTOS is small consuming 2K of RAM
Ram
-Animals:*Ram, an uncastrated male sheep*Ram cichlid, a species of freshwater fish endemic to Colombia and Venezuela-Military:*Battering ram*Ramming, a military tactic in which one vehicle runs into another...
and using 18K of flash
Flash memory
Flash memory is a non-volatile computer storage chip that can be electrically erased and reprogrammed. It was developed from EEPROM and must be erased in fairly large blocks before these can be rewritten with new data...
, while "RK" is short for Resource Kernel. A resource kernel provides reservations on how often system resources can be consumed. For example, a task
Task (computers)
A task is an execution path through address space. In other words, a set of program instructions that are loaded in memory. The address registers have been loaded with the initial address of the program. At the next clock cycle, the CPU will start execution, in accord with the program. The sense is...
might only be allowed to execute 10ms every 150ms (CPU Reservation), or a node
Node (networking)
In communication networks, a node is a connection point, either a redistribution point or a communication endpoint . The definition of a node depends on the network and protocol layer referred to...
might only be allowed to transmit 10 network packets per minute (Network Reservation). These reservations form a virtual energy budget
Energy budget
An energy budget is a balance sheet of energy income against expenditure. It is studied in the field of Energetics which deals with the study of energy transfer and transformation from one form to another. Calorie is the basic unit of measurement...
to ensure a node meets its designed battery lifetime as well as protects a failed node from generating excessive network traffic. Nano-RK is open source
Open source
The term open source describes practices in production and development that promote access to the end product's source materials. Some consider open source a philosophy, others consider it a pragmatic methodology...
, written in C
C (programming language)
C is a general-purpose computer programming language developed between 1969 and 1973 by Dennis Ritchie at the Bell Telephone Laboratories for use with the Unix operating system....
and runs on the Atmel
Atmel
Atmel Corporation is a manufacturer of semiconductors, founded in 1984. Its focus is on system-level solutions built around flash microcontrollers...
based FireFly sensor networking platform, the MicaZ motes as well as the MSP430 processor.
The following article discusses some of the tradeoffs associated with using an RTOS in sensor networks.