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CPU

A central processing unit, also called a central processor, main processor, or just processor, is the electronic circuitry that executes instructions comprising a computer program. The CPU performs basic arithmetic, logic, controlling, and input/output operations specified by the instructions in the program. CPU

What Happens When A CPU Starts

  • Generally, when a CPU chip first receives power, it must be reset by receiving a pulse on its RESET (or RST) pin
  • the Z80 CPU immediately begins executing code from memory address 0000 when it is reset. This is a relatively simple case
  • By contrast, the 6502, another popular classic CPU, has a two-byte reset vector located at memory addresses FFFC and FFFD (in hexadecimal). This means that the ROM in a 6502-based computer must be at the top of the memory space. The two bytes are stored backwards, and thus, if FFFC contains 00 and FFFD contains B0, then the 6502 will jump to memory location B000 and start executing instructions there
  • There are two advantages to this system: First of all, it gives the computer engineer some control over where the CPU begins executing ROM code, and secondly, it leaves the bottom area of the memory space (beginning at address 0000) free for RAM
  • The Z80's system, although simpler, creates a "hole" in the memory, because the bottom of the memory space is used by ROM and therefore you cannot use the beginning of the memory space for normal RAM work

Links to This Note

WebNPU API를 상상하다

... - WebAssembly는 웹에서CPU의 온전한 성능을 개방한다.

Web Worker

... are often able to utilize multi-coreCPUsmore effectively. [Web worker](https://en.wikipedia.org/wiki/Web_worker) ...

Vertex Buffer

... Graphics. How to pass instructions fromCPUto GPU. ...

VP9 vs HEVC

... were decoded on CPUs, using theCPU400%. ...

Spectre

... of the two original transient executionCPUvulnerabilities (Meltdown), which involve microarchitectural timing ...

SIMD

... - Pushes many data intoCPUchannels in a parallel way ...

Principles of Inclusion

... - Higher level (closer toCPU) always contains a subset of ...

Preemptive Multitasking

... Therefore, all processes will get someCPUtime at any given time. [Preemption ...

Meltdown and Spectre

... - Spectre makes theCPUjump to the wrong place and ...

Meltdown

... of the two original transient executionCPUvulnerabilities (the other being Spectre). Meltdown ...

JVM

... set of instructions that a computer'sCPUexecutes directly. ...

Imagining WebNPU API

... WebAssembly unlocks the bare-metal power ofCPUs.

How to Build Software like an SRE

... - keep error logs,CPUusage, and request error rates ...

How is WebAssembly cross-platform when Assembly is not

... multiple precompiled binary executables for multipleCPUvendors, like Apple's Universal Binary? ...

Databricks AI Summit 2023 Block Session

... open-source models, allowing for swapping betweenCPU, GPU, and models like MPT.

ChatGPT는 흐릿한 이미지이지만 필요합니다

... 예전에CPU의 달력 스케일을 시각화하는 흥미로운 사고 ...

ChatGPT is a Blurry JPEG and We Need That

... visualized the calendar scale of aCPU. Imagine that one cycle of ...

2023-01-13

... -CPU