01 - embedded learning route and career planning: embedded basic knowledge and development process

01 - Embedded learning route 、 Occupation planning

One 、 Career gossip —— （ Learning route / Industry Introduction ）

1. What is embedded ？

• In addition to general-purpose computers （ The boundaries begin to blur ： Like raspberry pie ）
• characteristic ：
  1. Hardware customization
  2. Intelligent control （ Computer technology ）
  3. Soft and hard cutting

2. Embedded related enterprises

• Smart home appliances ： haier 、 hisense 、TCL…
• Communication equipment field ： Huawei 、 zte 、 millet …
• Automotive electronics ： BYD 、 geely …
• Integrated circuit field 、 New display field, etc …

3. Learn the reference route

• College students' ： Count the electricity 、 Mode electricity 、C Language
• Entry stage ：MCU Hardware 、MCU Software
• Growing period ： SCM logic 、RTOS、Linux/Android drive 、Linux application 、 other DSP/FPGA（ Can be used as an auxiliary skill , It's more difficult , Fewer jobs ）
• mature period ： project manager （ management ）、 Senior Engineer （ technology ）

4. Basic internal skill of learning

• C Language 、 data structure （ Linked list 、 Stack, etc ）
• digital circuit 、 Analog circuit （ Understand the schematic diagram and basic circuit ）
• English , Understand the chip manual
• A multimeter 、 Oscilloscope / Logic analyzer 、 Electric iron

Two 、 Basic concepts —— ARM/STM32/MCU/MPU

1. What is? ARM？

• A design processor architecture company
• use ARM The company provides scheme design Processor chips are collectively referred to as
• ARM(Advanced RISC Machines)

** Reduced instruction set computer （RISC:Reduced Instruction Set Computer)** It is a computer with short instruction length , Its running speed is faster than CISC Be quick .RISC and CISC yes CPU From the characteristics of instruction set, it can be divided into two categories ：CISC and RISC.RISC It's English Reduced Instruction Set Computer Abbreviation , Namely “ Reduced instruction set ”,CISC Namely “ Complex instruction set ”.RISC The instruction system is relatively simple , It only requires the hardware to execute the most commonly used part of the instructions , Most complex operations use sophisticated compilation techniques , Synthesized from simple instructions . At present, this instruction system is widely used in medium and high-grade servers CPU, In particular, all high-end servers adopt RISC Of the instruction system CPU. Adopt... In medium and high-grade servers RISC The directive CPU There are mainly Compaq（ compaq , New HP ） The company's Alpha、HP The company's PA-RISC、IBM The company's Power PC、MIPS The company's MIPS and SUN The company's Sparc.

2.ARM Classification of Architecture

Cortex —
A : application processor Application type The system has the strongest capability and performance
R : real time controller Real time controller type （ Rare )
M : microcontroller processor Microcontroller type The system capability and performance are the weakest

3.MCU and MPU

• MCU：micro-controller unit , Micro controller
• MPU：micro-processor unit, Microprocessor , Strong computing power

difference ：MCU built-in RAM and Flash,MPU External location RAM and Flash , The boundaries are blurring

4.DSP and FPGA

• DSP：
  • digital signal processing： Digital signal processing , Indicates a type of function
  • digital signal processor： Digital signal processor , A particular kind of chip
• FPGA：
  • field-programmabl gate array： Programmable gate array , Functions can be changed , Used in some special occasions

3、 ... and 、 Development process —— SCM development process

1. Cross development

• technological process ： The host machine （ The computer ）—— debugging / Downloader —— Target machine （ Development board ）
• Reasons for cross development ： Embedded development target machine （ Development board ） Limited resources , So in the host （ The computer ） Programming on , By debugging / The downloader will burn the target file to the target machine .

2. The host machine （ Integrated development environment ）

Integrated development environment IDE, That is, the editor 、 compiler 、 Assembler 、 The connector 、 The debugger inherits together .

• Single chip microcomputer development commonly used software ：
  • Keil： Most widely used , Only support ARM（ Early support 51, After being ARM Acquisition ）
  • stm32cubeide： Only support stm21 Series MCU
  • IAR： In addition to ARM External chip

3. debugging / download ：

• Tools ：J-Link,ST-Link（ Support single step debugging ）
• agreement ：JTAG/SWD,ARM All support JTAG

4. Target machine （ Development board ）

• Debug the development board ： adopt USB-TTL Serial port and host computer （ The drive needs to be installed ） Communication printing information

Four 、 Development board Introduction

• I want to learn from Mr. weidongshan RTOS Course and introduction to the Internet of things , So I didn't buy the development board . Course supporting stm32 The development board is designed for Baiwen , It's on sale on Taobao , Relevant documents can be downloaded for free on the official website . I would like to make a special recommendation here FreeRTOS A tutorial for ,《FreeRTOS Full development manual 》 You can get started quickly RTOS, The principle explanation and project code analysis are in B There is a free video on . If you want to do this experiment, you only need one piece stm32 And Esp8266 The module of .

• I would like to recommend Mr. weidongshan's courses to you , Such as FreeRTOS and Linux etc. , They all start from the principle , Then I will show you the source code , Finally, the computer experiment is carried out . It's not just about api Use , Dry a lot , Before, Mr. Wei mainly did Linux course , Maybe for this reason , Speak up FreeRTOS More in-depth , Baiwen （https://www.100ask.net/index） and B There are some free videos on the website .