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OpenRISC 1200
The OpenRISC 1200 (OR1200) is an implementation of the open source OpenRISC 1000 RISC architectur. A soft microprocessor, synthesizable CPU core, it was for many years maintained by developers at OpenCores.org, although, since 2015, that activity has now been taken over by the Free and Open Source Silicon Foundation at thlibrecores.orgwebsite. The Verilog RTL description is released under the GNU Lesser General Public License (LGPL). Architecture The IP core of the OR1200 is implemented in the Verilog HDL. As an open source core, the design is fully public and may be downloaded and modified by any individual. The official implementation is maintained by developers at OpenCores.org. The implementation specifies a power management unit, debug unit, tick timer, programmable interrupt controller (PIC), central processing unit (CPU), and memory management hardware. Peripheral systems and a memory subsystem may be added using the processor's implementation of a standardized 3 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OR1200
The OpenRISC 1200 (OR1200) is an implementation of the open source OpenRISC 1000 RISC architectur. A soft microprocessor, synthesizable CPU core, it was for many years maintained by developers at OpenCores.org, although, since 2015, that activity has now been taken over by the Free and Open Source Silicon Foundation at thlibrecores.orgwebsite. The Verilog RTL description is released under the GNU Lesser General Public License (LGPL). Architecture The IP core of the OR1200 is implemented in the Verilog HDL. As an open source core, the design is fully public and may be downloaded and modified by any individual. The official implementation is maintained by developers at OpenCores.org. The implementation specifies a power management unit, debug unit, tick timer, programmable interrupt controller (PIC), central processing unit (CPU), and memory management hardware. Peripheral systems and a memory subsystem may be added using the processor's implementation of a standardized ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Field-programmable Gate Array
A field-programmable gate array (FPGA) is an integrated circuit designed to be configured by a customer or a designer after manufacturinghence the term '' field-programmable''. The FPGA configuration is generally specified using a hardware description language (HDL), similar to that used for an application-specific integrated circuit (ASIC). Circuit diagrams were previously used to specify the configuration, but this is increasingly rare due to the advent of electronic design automation tools. FPGAs contain an array of programmable logic blocks, and a hierarchy of reconfigurable interconnects allowing blocks to be wired together. Logic blocks can be configured to perform complex combinational functions, or act as simple logic gates like AND and XOR. In most FPGAs, logic blocks also include memory elements, which may be simple flip-flops or more complete blocks of memory. Many FPGAs can be reprogrammed to implement different logic functions, allowing flexible reconfigur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UClibc
__NOTOC__ In computing, uClibc (sometimes written µClibc) is a small C standard library intended for Linux kernel-based operating systems for embedded systems and mobile devices. uClibc was written to support μClinux, a version of Linux not requiring a memory management unit and thus suited for microcontrollers (uCs; the "u" is a Latin script typographical approximation - not a proper romanization, which would be letter "m" - of μ for "micro"). Development on uClibc started around 1999. uClibc was mostly written from scratch, but has incorporated code from glibc and other projects. The project lead is Erik Andersen, and the other main contributor is Manuel Novoa III. Licensed under the GNU Lesser General Public License, uClibc is free and open-source software. uClibc is much smaller than the glibc, the C library normally used with Linux distributions. While glibc is intended to fully support all relevant C standards across a wide range of hardware and kernel platforms, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Newlib
Newlib is a C standard library implementation intended for use on embedded systems. It is a conglomeration of several library parts, all under free software licenses that make them easily usable on embedded products. It was created by Cygnus Support as part of building the first GNU cross-development toolchains. It is now maintained by Red Hat developers Jeff Johnston and Corinna Vinschen, and is used in most commercial and non-commercial GCC ports for non-Linux embedded systems. System Calls The section System Calls of the Newlib documentation describes how it can be used with many operating systems. Its primary use is on embedded systems that lack any kind of operating system; in that case it calls a board support package that can do things like write a byte of output on a serial port, or read a sector from a disk or other memory device. Inclusion Newlib is included in commercial GCC distributions by Atollic, CodeSourcery, Code Red, KPIT, Red Hat and others, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linux Kernel
The Linux kernel is a free and open-source, monolithic, modular, multitasking, Unix-like operating system kernel. It was originally authored in 1991 by Linus Torvalds for his i386-based PC, and it was soon adopted as the kernel for the GNU operating system, which was written to be a free (libre) replacement for Unix. Linux is provided under the GNU General Public License version 2 only, but it contains files under other compatible licenses. Since the late 1990s, it has been included as part of a large number of operating system distributions, many of which are commonly also called Linux. Linux is deployed on a wide variety of computing systems, such as embedded devices, mobile devices (including its use in the Android operating system), personal computers, servers, mainframes, and supercomputers. It can be tailored for specific architectures and for several usage scenarios using a family of simple commands (that is, without the need of manually editing its source code ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GNU Compiler Collection
The GNU Compiler Collection (GCC) is an optimizing compiler produced by the GNU Project supporting various programming languages, hardware architectures and operating systems. The Free Software Foundation (FSF) distributes GCC as free software under the GNU General Public License (GNU GPL). GCC is a key component of the GNU toolchain and the standard compiler for most projects related to GNU and the Linux kernel. With roughly 15 million lines of code in 2019, GCC is one of the biggest free programs in existence. It has played an important role in the growth of free software, as both a tool and an example. When it was first released in 1987 by Richard Stallman, GCC 1.0 was named the GNU C Compiler since it only handled the C programming language. It was extended to compile C++ in December of that year. Front ends were later developed for Objective-C, Objective-C++, Fortran, Ada, D and Go, among others. The OpenMP and OpenACC specifications are also supported in the C and C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GNU Toolchain
The GNU toolchain is a broad collection of programming tools produced by the GNU Project. These tools form a toolchain (a suite of tools used in a serial manner) used for developing software applications and operating systems. The GNU toolchain plays a vital role in development of Linux, some BSD systems, and software for embedded systems. Parts of the GNU toolchain are also directly used with or ported to other platforms such as Solaris, macOS, Microsoft Windows (via Cygwin and MinGW/MSYS), Sony PlayStation Portable (used by PSP modding scene) and Sony PlayStation 3. Components Projects included in the GNU toolchain are: * GNU make: an automation tool for compilation and build * GNU Compiler Collection (GCC): a suite of compilers for several programming languages * GNU C Library (glibc): core C library including headers, libraries, and dynamic loader * GNU Binutils: a suite of tools including linker, assembler and other tools * GNU Bison: a parser generator, often used with th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dhrystone
Dhrystone is a synthetic computing benchmark program developed in 1984 by Reinhold P. Weicker intended to be representative of system (integer) programming. The Dhrystone grew to become representative of general processor ( CPU) performance. The name "Dhrystone" is a pun on a different benchmark algorithm called Whetstone (pun explained: w''h''et-stone = wet-stone , d''h''ry-stone = dry-stone), which emphasizes floating point performance. With Dhrystone, Weicker gathered meta-data from a broad range of software, including programs written in FORTRAN, PL/1, SAL, ALGOL 68, and Pascal. He then characterized these programs in terms of various common constructs: procedure calls, pointer indirections, assignments, etc. From this he wrote the Dhrystone benchmark to correspond to a representative mix. Dhrystone was published in Ada, with the C version for Unix developed by Rick Richardson ("version 1.1") greatly contributing to its popularity. Dhrystone vs. Whetstone The Dhrysto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CPU Cache
A CPU cache is a hardware cache used by the central processing unit (CPU) of a computer to reduce the average cost (time or energy) to access data from the main memory. A cache is a smaller, faster memory, located closer to a processor core, which stores copies of the data from frequently used main memory locations. Most CPUs have a hierarchy of multiple cache levels (L1, L2, often L3, and rarely even L4), with different instruction-specific and data-specific caches at level 1. The cache memory is typically implemented with static random-access memory (SRAM), in modern CPUs by far the largest part of them by chip area, but SRAM is not always used for all levels (of I- or D-cache), or even any level, sometimes some latter or all levels are implemented with eDRAM. Other types of caches exist (that are not counted towards the "cache size" of the most important caches mentioned above), such as the translation lookaside buffer (TLB) which is part of the memory management unit (MMU) w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Translation Lookaside Buffer
A translation lookaside buffer (TLB) is a memory cache that stores the recent translations of virtual memory to physical memory. It is used to reduce the time taken to access a user memory location. It can be called an address-translation cache. It is a part of the chip's memory-management unit (MMU). A TLB may reside between the CPU and the CPU cache, between CPU cache and the main memory or between the different levels of the multi-level cache. The majority of desktop, laptop, and server processors include one or more TLBs in the memory-management hardware, and it is nearly always present in any processor that utilizes paged or segmented virtual memory. The TLB is sometimes implemented as content-addressable memory (CAM). The CAM search key is the virtual address, and the search result is a physical address. If the requested address is present in the TLB, the CAM search yields a match quickly and the retrieved physical address can be used to access memory. This is called a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
