Programmer Think

What is critical section A critical segment is a piece of code that cannot be interrupted by internal interrupts during execution. In FreeRTOS, the most common critical segment is the operation of global variables. Global variables are like a gun handle. Anyone can shoot him, but when I shoot, you can't shoot, otherwise you don't know who hit ...

Start process There are two main startup processes for FreeRTOS In the main function, initialize the hardware, RTOS system and create all tasks. Finally, start the RTOS scheduler to start multi task scheduling. (create first, then schedule) int main (void) { /* Hardware initialization */ HardWare_Init(); /* RTOS System initiali ...

The design idea of the divider is more complex, mainly shift and divide. Put the divisor and the dividend in registers B and A respectively, and then add A shift register R with the same bit width n. 8 'b0 in R is used as the high bit and the data in A is used as the low bit. The operation process requires 2n clock cycles. The process is like t ...

Why use C + + to develop MCU program In the embedded system with microprocessor as the core, most of them use C language for program design, but with the increase of system scale, the program is more and more complex and maintenance is more and more difficult. Using C + + for development has the following advantages (provided that the compiler ...

Chitu V307 (CH32V307) is a RISC-V core MCU, which is equipped with qinheng self-developed RISC-V core highland barley V4F, with a maximum dominant frequency of 144MHz and supports single precision floating-point operation (FPU). Generally, the size of Flash is 256 KB and the size of SRAM is 64 KB. After carefully reading the application manu ...

For example, how can we dig holes from the United States to China faster Use a shovel to dig from every 2 seconds to every 1 second. There is an upper limit. If it is too fast, the shovel will break (increasing the clock frequency of the processor will increase the energy consumption, and there is an upper limit on the energy consumptio ...

ESP32 MCU learning notes - 02 - Software IIC & hardware SPI Preface, continue the content of the previous article. In order not to accumulate too much content, write it separately. 1, ESP32 read gyroscope (IIC) Official routine: github:esp-idf/examples/peripherals/i2c/i2c_self_test/ iic is the official software used by iic before ...

Analysis of errors in AFIO clock AFIO misunderstanding We generally misunderstand it as "enabling the multiplexing function of the IO port requires enabling the AFIO clock", but let's recall the structure diagram of GPIO and learn more about GPIOx_Pin structure:   In the figure above, the signal from the port pin enters the mult ...

LCD driver under Linux In linux driver development, it is essential to use lcd for human-computer interaction. Therefore, how can we initialize lcd in the kernel? 1. LCD screen IO configuration Open dts device tree file, create lcd child nodes in iomuxc pinctrl_lcdif_dat: lcdifdatgrp { fsl,pins = < MX6UL_PAD_LCD_DATA00__LCDIF_DATA00 0 ...

catalogue preface Specific manifestations of can line problem: Software problems: 1. Speed 2. Pin 3. Interrupt callback summary preface After studying stm32 for a period of time, I have summarized some common problems. This article mainly writes about the problems encountered on the can line. Specific manifestations of ...