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Intel 80376
The Intel 80376, introduced January 16, 1989, was a variant of the Intel 80386SX intended for embedded systems. It differed from the 80386 in not supporting real mode (the processor booted directly into protected mode) and having no support for paging in the Memory management unit, MMU. The 376 was available at 16 or 20 MHz clock rates. This processor can perform up to 3.0 Instructions_per_second#Millions_of_instructions_per_second_(MIPS), MIPS at 16 MHz speed. The Intel 82370 chipset which contains 8 Direct memory access, DMA channels, 15 Interrupt, interrupts, 4 16-bit Programmable interval timer, timer/counters, DRAM Memory refresh, refresh controller, and Wait state, wait-state generator which it is closely coupled with this processor, but it is software compatible to Intel 82380 chipset. Both devices are packaged with 100-pin BQFP. The 80376 and the 82370 version have also have 88-Pin grid array, PGA and 132-PGA package as well respectfully. The plastic version of 80 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
KL Intel I376
KL, kL, kl, or kl. may refer to: Businesses and organizations * KLM, a Dutch airline (IATA airline designator KL) * Royal Netherlands Army, Koninklijke Landmacht, the Royal Netherlands Army * Women's List, Kvenna Listin ("Women's List"), a political party in Iceland * KL FM, a Malay language radio station Places * Kaiserslautern, Germany (license plate code KL) * Kerala, India (ISO 3166-2:IN subcode KL) * Kirkland Lake, Ontario, Canada * Kowloon, Hong Kong * Kuala Lumpur, Malaysia Science, technology, and mathematics * KL engine, version of the Mazda K engine * Klepton (kl.), a type of species in zoology * Kiloliter (kL), a unit of volume * Kullback–Leibler divergence in mathematics * KL (gene), a gene which encodes the klotho enzyme in humans Other uses * Jeep Cherokee (KL) * Kalaallisut language (ISO 639 alpha-2 language code "kl") * Kl (digraph), used in the Zulu language to write /kʟ̥ʼ/ or /kxʼ/ * Konzentrationslager, or concentration camp, abbreviated KZ or KL * ''KL â ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Direct Memory Access
Direct memory access (DMA) is a feature of computer systems and allows certain hardware subsystems to access main system memory independently of the central processing unit (CPU). Without DMA, when the CPU is using programmed input/output, it is typically fully occupied for the entire duration of the read or write operation, and is thus unavailable to perform other work. With DMA, the CPU first initiates the transfer, then it does other operations while the transfer is in progress, and it finally receives an interrupt from the DMA controller (DMAC) when the operation is done. This feature is useful at any time that the CPU cannot keep up with the rate of data transfer, or when the CPU needs to perform work while waiting for a relatively slow I/O data transfer. Many hardware systems use DMA, including disk drive controllers, graphics cards, network cards and sound cards. DMA is also used for intra-chip data transfer in multi-core processors. Computers that have DMA channels can trans ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pin Grid Array
A pin grid array (PGA) is a type of integrated circuit packaging. In a PGA, the package is square or rectangular, and the pins are arranged in a regular array on the underside of the package. The pins are commonly spaced 2.54 mm (0.1") apart, and may or may not cover the entire underside of the package. PGAs are often mounted on printed circuit boards using the through hole method or inserted into a socket. PGAs allow for more pins per integrated circuit than older packages, such as dual in-line package (DIP). PGA variants Plastic Plastic pin grid array (PPGA) packaging was used by Intel for late-model Mendocino core Celeron processors based on Socket 370. Some pre-Socket 8 processors also used a similar form factor, although they were not officially referred to as PPGA. Flip chip A flip-chip pin grid array (FC-PGA or FCPGA) is a form of pin grid array in which the die faces downwards on the top of the substrate with the back of the die exposed. This allows ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BQFP
A quad flat package (QFP) is a surface-mounted integrated circuit package with "gull wing" leads extending from each of the four sides. Socketing such packages is rare and through-hole mounting is not possible. Versions ranging from 32 to 304 pins with a pitch ranging from 0.4 to 1.0 mm are common. Other special variants include low-profile QFP (LQFP) and thin QFP (TQFP). The QFP component package type became common in Europe and United States during the early nineties, even though it has been used in Japanese consumer electronics since the seventies. It is often mixed with hole mounted, and sometimes socketed, components on the same printed circuit board (PCB). A package related to QFP is plastic leaded chip carrier (PLCC) which is similar but has pins with larger pitch, 1.27 mm (or 1/20 inch), curved up underneath a thicker body to simplify socketing (soldering is also possible). It is commonly used for NOR flash memories and other programmable components. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wait State
A wait state is a delay experienced by a computer processor when accessing external memory or another device that is slow to respond. Computer microprocessors generally run much faster than the computer's other subsystems, which hold the data the CPU reads and writes. Even memory, the fastest of these, cannot supply data as fast as the CPU could process it. In an example from 2011, typical PC processors like the Intel Core 2 and the AMD Athlon 64 X2 run with a clock of several GHz, which means that one clock cycle is less than 1 nanosecond (typically about 0.3 ns to 0.5 ns on modern desktop CPUs), while main memory has a latency of about 15–30 ns. Some second-level CPU caches run slower than the processor core. When the processor needs to access external memory, it starts placing the address of the requested information on the address bus. It then must wait for the answer, that may come back tens if not hundreds of cycles later. Each of the cycles spent waiting is called a wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Memory Refresh
Memory refresh is the process of periodically reading information from an area of computer memory and immediately rewriting the read information to the same area without modification, for the purpose of preserving the information."refresh cycle" in Memory refresh is a background maintenance process required during the operation of semiconductor dynamic random-access memory (DRAM), the most widely used type of computer memory, and in fact is the defining characteristic of this class of memory. In a DRAM chip, each bit of memory data is stored as the presence or absence of an electric charge on a small capacitor on the chip. As time passes, the charges in the memory cells leak away, so without being refreshed the stored data would eventually be lost. To prevent this, external circuitry periodically reads each cell and rewrites it, restoring the charge on the capacitor to its original level. Each memory refresh cycle refreshes a succeeding area of memory cells, thus repeatedly re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Programmable Interval Timer
In computing and in embedded systems, a programmable interval timer (PIT) is a counter that generates an output signal when it reaches a programmed count. The output signal may trigger an interrupt. Common features PITs may be one-shot or periodic. One-shot timers will signal only once and then stop counting. Periodic timers signal every time they reach a specific value and then restart, thus producing a signal at periodic intervals. Periodic timers are typically used to invoke activities that must be performed at regular intervals. Counters are usually programmed with fixed intervals that determine how long the counter will count before it will output a signal. IBM PC compatible The Intel 8253 PIT was the original timing device used on IBM PC compatibles. It used a 1.193182 MHz clock signal (one third of the color burst frequency used by NTSC, one twelfth of the system clock crystal oscillator, therefore one quarter of the 4.77 MHz CPU clock) and contains three timers. Timer 0 i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interrupt
In digital computers, an interrupt (sometimes referred to as a trap) is a request for the processor to ''interrupt'' currently executing code (when permitted), so that the event can be processed in a timely manner. If the request is accepted, the processor will suspend its current activities, save its state, and execute a function called an ''interrupt handler'' (or an ''interrupt service routine'', ISR) to deal with the event. This interruption is often temporary, allowing the software to resume normal activities after the interrupt handler finishes, although the interrupt could instead indicate a fatal error. Interrupts are commonly used by hardware devices to indicate electronic or physical state changes that require time-sensitive attention. Interrupts are also commonly used to implement computer multitasking, especially in real-time computing. Systems that use interrupts in these ways are said to be interrupt-driven. Types Interrupt signals may be issued in response to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Instructions Per Second
Instructions per second (IPS) is a measure of a computer's processor speed. For complex instruction set computers (CISCs), different instructions take different amounts of time, so the value measured depends on the instruction mix; even for comparing processors in the same family the IPS measurement can be problematic. Many reported IPS values have represented "peak" execution rates on artificial instruction sequences with few branches and no cache contention, whereas realistic workloads typically lead to significantly lower IPS values. Memory hierarchy also greatly affects processor performance, an issue barely considered in IPS calculations. Because of these problems, synthetic benchmarks such as Dhrystone are now generally used to estimate computer performance in commonly used applications, and raw IPS has fallen into disuse. The term is commonly used in association with a metric prefix (k, M, G, T, P, or E) to form kilo instructions per second (kIPS), million instructions p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intel 80386SX
The Intel 386, originally released as 80386 and later renamed i386, is a 32-bit microprocessor introduced in 1985. The first versions had 275,000 transistorsmit.edu—The Future of FPGAs (Cornell) October 11, 2012 and were the central processing unit, CPU of many workstations and high-end personal computers of the time. As the original implementation of the 32-bit computing, 32-bit extension of the Intel 80286, 80286 architecture, the i386 instruction set, programming model, and binary encodings are still the Instruction selection#Lowest common denominator strategy, common denominator for all 32-bit x86 processors, which is termed the ''i386-architecture'', ''x86'', or ''IA-32'', depending on context. The 32-bit i386 can correctly execute ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clock Rate
In computing, the clock rate or clock speed typically refers to the frequency at which the clock generator of a processor can generate pulses, which are used to synchronize the operations of its components, and is used as an indicator of the processor's speed. It is measured in the SI unit of frequency hertz (Hz). The clock rate of the first generation of computers was measured in hertz or kilohertz (kHz), the first personal computers (PCs) to arrive throughout the 1970s and 1980s had clock rates measured in megahertz (MHz), and in the 21st century the speed of modern CPUs is commonly advertised in gigahertz (GHz). This metric is most useful when comparing processors within the same family, holding constant other features that may affect performance. Determining factors Binning Manufacturers of modern processors typically charge premium prices for processors that operate at higher clock rates, a practice called binning. For a given CPU, the clock rates are determined at th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Memory Management Unit
A memory management unit (MMU), sometimes called paged memory management unit (PMMU), is a computer hardware unit having all memory references passed through itself, primarily performing the translation of virtual memory addresses to physical addresses. An MMU effectively performs virtual memory management, handling at the same time memory protection, cache control, bus arbitration and, in simpler computer architectures (especially 8-bit systems), bank switching. Overview Modern MMUs typically divide the virtual address space (the range of addresses used by the processor) into pages, each having a size which is a power of 2, usually a few kilobytes, but they may be much larger. The bottom bits of the address (the offset within a page) are left unchanged. The upper address bits are the virtual page numbers. Page table entries Most MMUs use an in-memory table of items called a "page table", containing one "page table entry" (PTE) per page, to map virtual page numbers to ph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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