The Qualcomm SA8155P chip supports various interface protocols. Below are some common interface protocols and related information: 1. MIPI Protocol MIPI DSI (Display Serial Interface): Used to connect the processor to the display (such as LCD, OLED), transmitting video data and control commands. It supports high resolutions (such as 4K) and high refresh rates, using … Read more
Note: Please indicate the source when reprinting, all rights reserved by the author.Note: This is based on my own understanding,if it conflicts with your principles and ideas, please forgive me and do not criticize. Environment Description None Introduction None EC20 Driver Porting and Testing Introduction to EC20 The EC20 is a fully compatible 4G module … Read more
Analysis of Linux USB Gadget ADB Driver This article briefly explains how to configure the USB ADB device through Configfs ffs. The typical block diagram of a working Linux ADB setup is shown below, primarily illustrating how the USB ADB device side operates. Host Side (Host): +———————————————–+ | Host Computer | | +———————+ +—————-+ | … Read more
Using Linux Libusb This article briefly explains how to write a Libusb application to read USB Mouse data. Libusb mainly supports synchronous and asynchronous communication methods, with corresponding Libusb interfaces introduced later. 1. Environment Preparation First, download the Libusb library. git clone https://github.com/libusb/libusb.git Compile the Libusb library. ./configure –disable-udev \ –host=arm-linux-gnueabi \ –build=x86_64-pc-linux-gnu \ –prefix=/gcc/linux-x86/aarch64/gcc-arm-10.3-2021.07-x86_64-aarch64-none-linux-gnu/bin/libusb/output … Read more
When it comes to the input interfaces of the MUB5, I would recommend Bluetooth first, as the MUB5’s Bluetooth is not only convenient but also delivers excellent sound quality, making it a connection method that is hard to let go of once you experience it. For the other methods, it mainly depends on what output … Read more
In the daily use and maintenance of Linux systems, mastering USB device information is key to troubleshooting and managing external devices. This article will introduce three commonly used commands to help you quickly obtain USB device details and efficiently manage devices. 1. lsusb: Quickly View Core Information lsusb is the most basic command for viewing … Read more
Learning USB for continuous improvement.To understand the USB device drivers under Linux, I started with USB Gadget. After extensive experimentation, I found that UAC1 does not support microphone creation. Therefore, I had to shift from configuring the KS file system to analyzing the source code. By analyzing the UAC1 source code (f_uac1.c), I realized that … Read more
Today, some students are worried that connecting a microcontroller development board to a computer via a USB cable might accidentally burn the computer. After all, a computer is much more expensive than a microcontroller. Today, let’s discuss this issue. 1. Why is it generally safe and unlikely to burn the computer? Currently, the most common … Read more
“ This article introduces the key principles and practices for correctly routing USB differential data lines on a PCB. The main goal is to achieve the 90-ohm impedance matching specified in the USB standards, while also considering ESD protection and a complete ground plane.“ USB Speed Levels and Impedance Requirements The USB speed standards have … Read more
Introduction Recently, I have been researching mechanical fault diagnosis and decided to create a small accelerometer, planning to use the STM32F1 as the main controller. Initially, I planned to use an external crystal oscillator as the main clock for the STM32, but to further reduce the size of the board, I decided to remove the … Read more