The folks at Lattice Semiconductor
have expanded their commitment to open source embedded system
design by releasing an implementation of the uClinux Operating System (OS) targeted for their LatticeMico32 embedded soft core processor.
The new OS support allows developers to rapidly implement control systems in a design flow that builds on Lattice's open source embedded solutions approach. It also complements the enhanced capabilities of the LatticeMico32 microprocessor core recently announced with the release of Lattice's ispLEVER version 7.0 SP2.
New features include slave-side arbitration for higher performance, enhanced peripheral support for improved integration, and support of the LatticeMico32 system design tool flow under Linux.
Lattice has also concurrently released a new version of the LatticeMico8 microcontroller that increases addressable code space and has configurable address range and improved stack operations for support of high-level compilers, while keeping a very small footprint.
Lattice contracted with Theobroma Systems of Austria to assist with the port of the uClinux OS to the LatticeMico32 microprocessor. Theobroma Systems has significant experience in embedded systems development of open source solutions. Their solutions portfolio ranges from creating customized board-support packages or development tools to turnkey projects based on embedded Linux.
The uClinux OS port to the LatticeMico32 offers a similar file system and the networking capabilities of Linux, but without an MMU. The port to the LatticeMico32 architecture (referred to as "lm32-nommu" by uClinux developers) is based on Linux2.6.
To provide a complete solution, the port includes current versions of uClinux "userland" applications, U-Boot, uClib, and uClinux-based user commands. Complete documentation is included with the port. Files needed for a demonstration on a LatticeECP2 evaluation board are available with the release, including the project files required to recreate the demo and begin development. Lattice provides development support on uClinux and Lattice FPGAs through its online uClinux technical forum, as well as its normal applications technical support process.
Enhancements to the LatticeMico32 Embedded Processor System include support for slave-side bus arbitration for overall improvement in system performance by allowing multiple bus masters, such as a DMA controller and the LatticeMico32 microprocessor, to communicate concurrently to different slave devices. The Mico System tool chain is now supported on the Linux operating system, and includes support for integrating the LatticeMico32 microprocessor and other Verilog IP from Lattice into a VHDL design.
Lattice provides a selection of IPexpress-compatible IP cores that are also available as peripherals to the LatticeMico32 microprocessor and are Mico System Builder ready. These cores, which include DDR, DDR2 and SDRAM memory controllers, a Tri-Speed Ethernet Media Access Controller and PCI 33MHz Target, among others, are automatically integrated into the Mico System Builder upon configuration in the IPexpress tool. Debug support has been enhanced with this release by the ability to daisy chain multiple designs, including the LatticeMico32 microprocessor, within the Reveal JTAG-based hardware debugger.
The LatticeMico8 microcontroller has also been enhanced to increase the breadth of embedded applications in which it can be employed. These include the ability to configure the number of lines of code possible and improved portability across FPGA architectures. The range of the branch operation has been increased fourfold to accommodate a larger code space. For improved support of high-level language compilers, the ability to configure the stack size has also been introduced.
Availability and pricing
All files related to the uClinux port are available for download from www.latticesemi.com/products/intellectualproperty (the LatticeMico32 IP web page). For quick evaluation of uClinux on the LatticeECP2 FPGA, Lattice provides the "LatticeMico32/DSP Development Board for LatticeECP2," which is used by the demo files supplied with the download. The board can be purchased for $695 from the Lattice online store. The LatticeMico32 and LatticeMico8 IP cores are offered by Lattice free of charge and along with their associated development tools are available from their respective web pages within the Lattice website.