embedded systems An embedded system is a computer system—a combination of a computer processor, computer memory, and input/output peripheral devices—that has a dedicated function within a larger mechanical or electronic system. It is ''embedded'' as ...

, a board support package (BSP) is the layer of

software Software is a set of computer programs and associated documentation and data. This is in contrast to hardware, from which the system is built and which actually performs the work. At the lowest programming level, executable code consists ...

containing hardware-specific

boot firmware In computing, booting is the process of starting a computer as initiated via Computer hardware, hardware such as a button or by a software command. After it is switched on, a computer's central processing unit (CPU) has no software in its ma ...

and

device driver In computing, a device driver is a computer program that operates or controls a particular type of device that is attached to a computer or automaton. A driver provides a software interface to hardware devices, enabling operating systems and ot ...

s and other routines that allow a given

embedded operating system An embedded operating system is an operating system for embedded computer systems. Embedded operating systems are computer systems designed to increase functionality and reliability for achieving a specific task. Resource efficiency comes at the ...

, for example a

real-time operating system A real-time operating system (RTOS) is an operating system (OS) for real-time applications that processes data and events that have critically defined time constraints. An RTOS is distinct from a time-sharing operating system, such as Unix, which m ...

(RTOS), to function in a given hardware environment (a

motherboard A motherboard (also called mainboard, main circuit board, mb, mboard, backplane board, base board, system board, logic board (only in Apple computers) or mobo) is the main printed circuit board (PCB) in general-purpose computers and other expand ...

), integrated with the embedded operating system.

Software

Third-party hardware developers who wish to support a given embedded operating system must create a BSP that allows that embedded operating system to run on their platform. In most cases, the embedded operating system image and

software license A software license is a legal instrument (usually by way of contract law, with or without printed material) governing the use or redistribution of software. Under United States copyright law, all software is copyright protected, in both source ...

, the BSP containing it, and the hardware are bundled together by the hardware vendor. BSPs are typically customizable, allowing the user to specify which drivers and routines should be included in the build based on their selection of hardware and software options. For instance, a particular single-board computer might be paired with several peripheral chips; in that case the BSP might include drivers for peripheral chips supported; when building the BSP image the user would specify which peripheral drivers to include based on their choice of hardware. Some suppliers also provide a root file system, a

toolchain In software, a toolchain is a set of programming tools that is used to perform a complex software development task or to create a software product, which is typically another computer program or a set of related programs. In general, the tools form ...

for building programs to run on the

embedded system An embedded system is a computer system—a combination of a computer processor, computer memory, and input/output peripheral devices—that has a dedicated function within a larger mechanical or electronic system. It is ''embedded'' as ...

, and utilities to configure the device (while running) along with the BSP. Many embedded operating system providers provide template BSP's, developer assistance, and test suites to aid BSP developers to set up an embedded operating system on a new hardware platform.

History

The term ''BSP'' has been in use since 1981 when Hunter & Ready, the developers of the

Versatile Real-Time Executive Versatile Real-Time Executive (VRTX) is a real-time operating system (RTOS) developed and marketed by the company Mentor Graphics. VRTX is suitable for both traditional board-based embedded systems and system on a chip (SoC) architectures. It ha ...

(VRTX), first coined the term to describe the

hardware-dependent software Hardware-dependent software (HDS or HdS), the part of an operating system that varies across microprocessor boards and is comprised notably of device drivers and of boot code which performs hardware initialization. HDS does not comprise code whi ...

needed to run VRTX on a specific hardware platform. Since the 1980s, it has been in wide use throughout the industry. Virtually all RTOS providers now use the term BSP.

Example

The

Wind River Systems Wind River Systems, also known as Wind River (trademarked as Wndrvr), is an Alameda, California–based company, subsidiary of Aptiv PLC. The company develops embedded system and cloud software consisting of real-time operating systems software, ...

board support package for the ARM Integrator 920T single-board computer contains, among other things, these elements: * A config.h file, which defines constants such as ROM_SIZE and RAM_HIGH_ADRS. * A

Makefile In software development, Make is a build automation tool that automatically builds executable programs and libraries from source code by reading files called ''Makefiles'' which specify how to derive the target program. Though integrated develo ...

, which defines binary versions of VxWorks ROM images for programming into

flash memory Flash memory is an electronic non-volatile computer memory storage medium that can be electrically erased and reprogrammed. The two main types of flash memory, NOR flash and NAND flash, are named for the NOR and NAND logic gates. Both us ...

. * A boot ROM file, which defines the boot line parameters for the board. * A target.ref file, which describes board-specific information such as switch and jumper settings, interrupt levels, and offset bias. * A

VxWorks VxWorks is a real-time operating system (or RTOS) developed as proprietary software by Wind River Systems, a wholly-owned subsidiary of Aptiv. First released in 1987, VxWorks is designed for use in embedded systems requiring real-time, determin ...

image. * Various C files, including: :flashMem.c—the device driver for the board's flash memory :pciIomapShow.c—mapping file for the PCI bus :primeCellSio.c—TTY driver :sysLib.c—system-dependent routines specific to this board :romInit.s—ROM initialization module for the board; contains entry code for images that start running from ROM Additionally the BSP is supposed to perform the following operations *Initialize the processor *Initialize the board *Initialize the RAM *Configure the segments *Load and run OS from flash

References

{{Embedded systems Booting Firmware Motherboard Embedded systems

Software

History

Example

See also

References