• [original] KVM QEMU analysis of Linux Virtualization (2) armv8 virtualization


    background Read the fucking source code!–By Lu Xun A picture is worth a thousand words.–By Gorky explain: KVM version: 5.9.1 QEMU version: 5.0.0 Tools: source insight 3.5, Visio 1. Overview KVM virtualization is inseparable from the support of underlying hardware. This paper will introduce the support of armv8 architecture processor for virtualization, including memory virtualization, […]

  • C Series 1 – Original Intention & brief introduction


    1、 Original intention Originally want liver algorithm or privately do it, but in a communication company will not C, work can not do therefore liver liver liver liver liver liver Liver, will not be very detailed, but as long as I write it out, I will not, or need to summarize, the following reference book […]

  • SYS.BASE -Operating system notes (Theory)


    operating system: provides basic abstraction of resource set to application program, controls the allocation of processor, memory and other I / O interface devices (Resource Management: time reuse, space reuse) among competing programs. Computer hardware: CPU: In each CPU base cycle, instructions are fetched from memory decoded (to determine its type and operation) – executed, […]

  • How to use mcp3421


    0 summary Due to the need of a project, weak voltage signal needs to be collected, and the voltage accuracy is required to be high. Therefore, mcp3421, an 18 Bit high-precision IIC AD conversion chip, is selected. In this paper, combined with the manual of mcp3421, the use of the chip is explained in detail, […]

  • C language 01 volatile keyword


    volatile It is a type modifier to remind the compiler that the variables it defines may change at any time. Therefore, every time a compiled program needs to store or read this variable, it will directly read data from the variable address (memory). If there is no volatile keyword, the compiler may optimize reading and […]

  • C serials 2 – compilation process and language history overview


    1、 The computer can be roughly divided into the following steps to add two numbers: 1. Copy a number from memory location 2000 to register 1; 2. Copy another digit from memory location 2004 to register 2; 3. Add the contents in register 2 with those in register 1, and store the result in register […]

  • The secret of CPU executing program is hidden in these 15 pictures


    preface So much code, you knowa = 1 + 2How is this code executed by the CPU? Software used so much, do you know the difference between 32-bit and 64 bit software? Can a 32-bit operating system run on a 64 bit computer? Can a 64 bit operating system run on a 32-bit computer? If […]

  • The National Day holiday is about eight days register


    I’ve compiled my previous articles into GitHub. Welcome to starhttps://github.com/crisxuan/b… Next, we will introduce the related contents of registers. We know that,registerIs the internal structure of the CPU, it is mainly used for information storage. In addition, there areArithmetic unit, responsible for data processing;controllerControl other components;External busConnect CPU and various components for data transmission;Internal busResponsible […]

  • Android power consumption (9) — Analysis of MTK power consumption


    1. Find wake up source <7>[ 129.680310] -(0)[913:system_server][name:mt_sleep&][SLP] @@@[email protected]@@ <4>[ 129.680310] -(0)[913:system_server][name:mt_spm_internal&][SPM] wake up ……………………. <7>[ 129.690364] .(0)[913:system_server][name:mt_sleep&][SLP] @@@[email protected]@@ The channel that generates EINT is recorded in EINT_ In the sta status register, this is the same for all platforms. As long as you know the value of this status register, you can know which […]

  • The use of UART in STM32 Hal Library


    initialization Let’s start with UART initialization1. Declare the initialization structure of UART and assign a value2. MX generated code will call Hal_ UART_ Mspinit(); to initialize UART. Of course, this code is also generated automatically. However, users can add operations they want to add in this function, including NVIC_ Configuration,DMA_ You can also add some […]

  • AT24C02 user mode IO read / write.md


    1. AT24C02 user mode IO read / write Based on the idea that everything is a file, the IO function can be used to read and write AT24C02 in Linux, which is usually read and written by single byte. Because the storage capacity of AT24C02 is not large, it has a weak impact on performance. […]

  • Beidou GPS synchronous clock makes acquisition system more accurate


    Beidou GPS synchronous clock makes acquisition system more accurate Beidou GPS synchronous clock makes acquisition system more accurate Beijing Zhun electronic technology official micro enterprise — ahjzsz Nowadays, there are many data acquisition systems, some based on DSP and some based on FPGA. Although the ability of collecting and processing data is not bad, most […]