Unison RTOS for Microcontrollers (MCUs), FPGAs and Microprocessors (MPUs)

RoweBots offers OEM developers ultra tiny Linux and POSIX compatible embedded or real-time operating systems (RTOS). The Unison Embedded Operating System or RTOS is the 32 bit offering and DSPnano RTOS is the 8/16 bit offering.  Unison supports general purpose microcontrollers (MCUs), digital signal processors (DSPs), FPGAs, microprocessors (MPUs) and digital signal controllers (DSCs) 32 bit architectures with as little as 1K of RAM and 2K of flash.

 Unison Features

  • Single process
  • Multiple thread
  • Micro-kernel based
  • Ultra tiny memory footprint
  • Embedded and real-time POSIX RTOS
  • Linux compatibility using POSIX RTOS approach
  • Supporting microcontrollers ( MCUs) , digital signal controllers (DSCs), digital signal processors (DSPs), microprocessors (MPUs) & FPGAs without an MMU.  
  • Memory protection capabilities provided.
  • Applications run as a single linked image loaded into Flash or RAM.
  • Microcontrollers from Renesas, TI, Fujitsu, ST Microelectronics, Microchip and others are fully supported with complete I/O support.
  • Microprocessors from TI are supported based on ARM Cortex A8 and A9.with complete I/O support.
  • FPGAs from Xilinx and Microsemi are supported including a broad set of I/O IP.
  • Ease of use is unsurpassed.
  • Integrated security modules, off the shelf for complete and uncompromising system security.
  • All capabilities are supported with demonstration programs allowing users to run these applications in 10 minutes out of the box on standard microcontroller (MCU), microprocessor (MPU), digital signal processor (DSP), digital signal controller (DSC) and FPGA hardware.

The tool environment is the preferred silicon vendor choice of IDE with additional options on some architectures. The compiler, assembler, linker and librarian are whatever is provided in the IDE as the default tool chain. All development is cross development from either a Windows or Linux host. The environment offers many optional tools. From Flash downloaders and the DSPnano RTOS Object Viewer through to Power On Self Test (IEC 60730) and a broad set of connectivity modules, the Unison Embedded Operating System or RTOS has a complete component and tool environment.

Unison applications are discussed under the applications section.

The Unison RTOS or embedded operating system kernel called Nanoexec offers the following kernel features:

  • pthreads
  • semaphores
  • mutexes
  • condition variables
  • message queues
  • join
  • barriers
  • memory managers
  • timers
  • clock
  • rendezvous
  • events
  • interrupt management
  • directory or name server capabilities
  • and more

The Unison Embedded Operating System or RTOS is layered on top of the Nanoexec kernel and provides the following additional features:

  • File I/O including file device mounting and formating
  • BSD socket interface including Select and other high level calls
  • A stdio library with buffered I/O mechanisms like fopen
  • Complete security solutions seamlessly integrated with the Unison RTOS

The Unison RTOS or  Embedded Operating System servers provide the actual I/O. They are completely self contained modules and include interrupt handlers, buffer management and translation from I/O requests into actual physical I/O.

See the detailed server man pages for details on the server features including:

  • Serial I/O
  • Multimedia file system
  • FAT file system
  • Flash file systems
  • PowerSafe File System
  • A POSIX shell called posh
  • TCP/UDP/IP with advanced features including NAT and a DHCP client
  • TCP/IPv6 with TCP/IPv4 and advanced filtering
  • Advanced networking including  TFTP, Telnet, PPP, DHCP server, Radius Client, SNMP and HTTP.
  • Wireless connectivity options including GPRS, WiFi, BlueTooth, Zigbee, AT server and Radio Module Interface
  • USB in various options
  • CAN
  • Security modules including TLS, IPSec, Secure email, HTTPS, Secure boot, SSH and SFTP.
  • And other connectivity modules.

Unison comes with application specific servers, tools and more with:

  • Motor control
  • Switched mode power supply control with data-logging and networking
  • Graphics with color touch panel support
  • LED lighting control system
  • Power On Self Test
  • Data-logging for development and field service
  • Downloading and booting options for field upgrades
  • Remedy RTOS Viewer, Timing Analysis and Debugging Tool
  • Remedy RED Remote Event and Data Analysis tool.
  • Secure boot and remote field support

Unison is ideal for Machine to Machine Communications (M2M)

The Unison Embedded Operating System or RTOS is ideally suited for machine to machine communications as well.  Unison RTOS offers the following features which map directly into the requirements seen for these applications.

  • Connectivity for a broad set of communication protocols
  • Support for a variety of file systems
  • A complete set of security protocols to allow your MCU, FPGA, MPU, DSP or DSC system to be locked down
  • An environment compatible with HTML5/Javascript web interfaces
  • Off the shelf support for remote management including device maintenance and remote field service.
  • Complete wireles support including LTE, GPRS/GSM, WiFi, Bluetooth, Zigbee, 6loWPAN and more.
  • Comprehensive development tools for debugging complex systems

Unison MCU RTOS fully supports the following MCUs and MPUs with complete Unison offerings with a nanokernel, POSIX interfaces, Internet protocols, USB, wireless, file systems, security protocols and Remedy tools.

  • Microchip PIC32 Family
  • Renesas RX Family
  • TI ARM Cortex A8:  Sitara, OMAP, DaVinci, Beagleboard, Beaglebone, 
  • TI ARM Stellaris - ARM Cortex M3
  • TI Tiva - ARM Cortex M4
  • ST STM32 ARM Cortex M0, M3, M4 : STM32 Family
  • NXP ARM Cortex M0, M3, M4 : LPC 1700, 1800
  • Fujitsu ARM Cortex M3 Mxx
  • Microsemi ARM Cortex M3 SmartFusion
  • Xilinx FPGA with Microblaze


The Unison Embedded Operating System or RTOS  has excellent documentation - refer to it for more details or look at the man pages here.

Unison RTOS or Unison Embedded Operating System offers all the features and components necessary for building embedded system products based on FPGAs, microcontrollers (MCUs) or microprocessors quickly and easily with the lowest time to market and the lowest total cost of ownership.  Unison RTOS or Embedded Operating System offers support for porting Linux applications quickly and easily using native POSiX APIs.

Support is provied on Microchip and Renesas microcontrollers, and digital signal controllers (PIC32, dsPIC, PIC24, RX, SH2A).  In the ARM Cortex world support is provided for ST Microelectronics, Texas Instruments (TI), NXP, Fujitsu, Microsemi and others (STM32, LPC 1700, 1800, TIVA, Stellaris, M9xxx, Smartfusion).  The Unison Embedded Operating System or RTOS with its ultra tiny embedded Linux capabilties also supports Xilinx microblaze.