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CompactRISC
CompactRISC is a family of instruction set architectures from National Semiconductor. The architectures are designed according to reduced instruction set computing principles, and are mainly used in microcontrollers. The subarchitectures of this family are the 16-bit CR16 and CR16C and the 32-bit CRX. CR16 architectures Features of CR16 family: compact implementations (less than 1 mm2 with 250 nm), addressing of 2 MB (2), frequencies up to 66 MHz, hardware multiplier for 16-bit integers. It has complex instructions such as bit manipulation, saving/restoring and push/pop of several registers with single command. CR16 has 16 general purpose registers of 16 bits, and address registers of 21 bits wide. There are 8 special registers: program counter, interrupt stack pointer ISP, interrupt vector address register INTBASE, status register PSR, configuration register and 3 debug registers. Status register implements flags: C, T, L, F, Z, N, E, P, I. Instructions are enc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Instruction Set Architecture
In computer science, an instruction set architecture (ISA), also called computer architecture, is an abstract model of a computer. A device that executes instructions described by that ISA, such as a central processing unit (CPU), is called an ''implementation''. In general, an ISA defines the supported instructions, data types, registers, the hardware support for managing main memory, fundamental features (such as the memory consistency, addressing modes, virtual memory), and the input/output model of a family of implementations of the ISA. An ISA specifies the behavior of machine code running on implementations of that ISA in a fashion that does not depend on the characteristics of that implementation, providing binary compatibility between implementations. This enables multiple implementations of an ISA that differ in characteristics such as performance, physical size, and monetary cost (among other things), but that are capable of running the same machine code, so that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Semiconductor
National Semiconductor was an American semiconductor manufacturer which specialized in analog devices and subsystems, formerly with headquarters in Santa Clara, California. The company produced power management integrated circuits, display drivers, audio and operational amplifiers, communication interface products and data conversion solutions. National's key markets included wireless handsets, displays and a variety of broad electronics markets, including medical, automotive, industrial and test and measurement applications. On September 23, 2011, the company formally became part of Texas Instruments as the "Silicon Valley" division. History Founding National Semiconductor was founded in Danbury, Connecticut, by Dr. Bernard J. Rothlein on May 27, 1959, when he and seven colleagues, Edward N. Clarke, Joseph J. Gruber, Milton Schneider, Robert L. Hopkins, Robert L. Koch, Richard R. Rau and Arthur V. Siefert, left their employment at the semiconductor division of Sperry Rand Corp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reduced Instruction Set Computing
In computer engineering, a reduced instruction set computer (RISC) is a computer designed to simplify the individual instructions given to the computer to accomplish tasks. Compared to the instructions given to a complex instruction set computer (CISC), a RISC computer might require more instructions (more code) in order to accomplish a task because the individual instructions are written in simpler code. The goal is to offset the need to process more instructions by increasing the speed of each instruction, in particular by implementing an instruction pipeline, which may be simpler given simpler instructions. The key operational concept of the RISC computer is that each instruction performs only one function (e.g. copy a value from memory to a register). The RISC computer usually has many (16 or 32) high-speed, general-purpose registers with a load/store architecture in which the code for the register-register instructions (for performing arithmetic and tests) are separate fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microcontroller
A microcontroller (MCU for ''microcontroller unit'', often also MC, UC, or μC) is a small computer on a single VLSI integrated circuit (IC) chip. A microcontroller contains one or more CPUs (processor cores) along with memory and programmable input/output peripherals. Program memory in the form of ferroelectric RAM, NOR flash or OTP ROM is also often included on chip, as well as a small amount of RAM. Microcontrollers are designed for embedded applications, in contrast to the microprocessors used in personal computers or other general purpose applications consisting of various discrete chips. In modern terminology, a microcontroller is similar to, but less sophisticated than, a system on a chip (SoC). An SoC may connect the external microcontroller chips as the motherboard components, but an SoC usually integrates the advanced peripherals like graphics processing unit (GPU) and Wi-Fi interface controller as its internal microcontroller unit circuits. Microcontrollers are use ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
250 Nanometer
The 250 nanometer (250 nm or 0.25 µm) process refers to a level of semiconductor process technology that was reached by most manufacturers in the 1997–1998 timeframe. Products featuring 250 nm manufacturing process *The DEC Alpha 21264A, which was made commercially available in 1999. *The AMD K6-2 ''Chomper'' and ''Chomper Extended''. Chomper was released on May 28, 1998. *The AMD K6-III "Sharptooth" used 250 nm. *The mobile Pentium MMX ''Tillamook'', released in August 1997. *The Pentium II '' Deschutes''. *The Pentium III '' Katmai''. *The Dreamcast's CPU and GPU. *The initial version of the Emotion Engine processor used in the PlayStation 2 The PlayStation 2 (PS2) is a home video game console developed and marketed by Sony Computer Entertainment. It was first released in Japan on 4 March 2000, in North America on 26 October 2000, in Europe on 24 November 2000, and in Australia on 3 .... *00250 Computer-related introductions in 1998 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
COP8
The National Semiconductor COP8 is an 8-bit CISC core microcontroller. COP8 is an enhancement to the earlier COP400 4-bit microcontroller family. COP8 main features are: * Large amount of I/O pins * Up to 32 KB of Flash memory/ROM for code and data * Very low EMI (no known bugs) * Many integrated peripherals (meant as single chip design) * In-System Programming * Free assembler toolchain. Commercial C compilers available * Free Multitasking OS and TCP/IP stack It has a machine cycle of up to 2M cycles per second, but most versions seem to be overclockable to up to 2.8M cycles per second (28 MHz clock). Registers and memory map The COP8 uses separate instruction and data spaces (Harvard architecture). Instruction address space is 15-bit (32 KiB maximum), while data addresses are 8-bit (256 bytes maximum, extended via bank-switching). To allow software bugs to be caught, all invalid instruction addresses read as zero, which is a trap instruction. Invalid RAM ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
