Recently, I have been researching the Bluetooth protocol stack and came across an interesting fact. We know that Apple’s AirPods have ushered in a new era of true wireless Bluetooth headphones (TWS), currently dominating a large share of the market. Many domestic manufacturers have followed suit, but due to Apple’s registered patents, they find themselves … Read more
This article is about classic Q&A on ADC/DAC design, covering common issues such as clock duty cycle, common mode voltage, gain error, differential phase error, intermodulation distortion, and more. 1. What is Small Signal Bandwidth (SSBW)?Small Signal Bandwidth (SSBW) refers to the frequency at which the output amplitude drops to a specified value compared to … Read more
Any practical electronic application will be affected by multiple sources of error, which can cause even the most precise components to deviate from their specified behavior in the datasheet. When the application signal chain lacks built-in mechanisms to self-correct these errors, the only way to minimize their impact is to measure the errors and systematically … Read more
In the field of digital signal processing, the Nyquist sampling theorem establishes the fundamental criterion for signal digitization— to accurately reconstruct a continuous signal, the sampling frequency must be at least twice the highest frequency of the signal.However, engineers have observed an interesting phenomenon: in practical applications, we often generate signals exceeding 500MHz using a … Read more
1. IntroductionLet’s take a look at a diagramFriends who have read the previous blog post “The Execution Process of CPU Instructions” should have noticed that there is an indispensable component in the execution process of instructions in a computer, which is the bus. The diagram above shows multiple buses, and today we will introduce in … Read more
Content Hello everyone, I am Bug Jun~In industrial communication and embedded development, RS485 has become one of the mainstream buses due to its high anti-interference capability and multi-node support. However, many engineers often confuse two key signals when debugging RS485: DE and RTS. They both appear to be “control send” signals, and in some circuits, … Read more
The SPI (Serial Peripheral Interface) is one of the most widely used synchronous serial communication protocols in embedded systems, playing a crucial role in STM32 development. Compared to I2C and UART, SPI is particularly suitable for high-speed data acquisition, memory expansion, and display driving due to its full-duplex communication, high transmission rates, and hardware slave … Read more
Implementing the SPI (Serial Peripheral Interface) driver on the STM32 microcontroller for communication with sensors. The content includes SPI initialization, data transmission, error handling, debugging techniques, and the use of logic analyzers. The code is based on the STM32Cube HAL library, suitable for the STM32F4 series (such as STM32F407), and uses a generic sensor (like … Read more
The previous article organized common communication interfaces I (RS232/RS485/USB/TYPE-C principles and differences), and in this article, we continue to organize the principles and differences of CAN, I2C, SPI, UART, and GPIO. 1.CAN Bus Interface 1)Definition CAN stands for Controller Area Network, developed by the German company BOSCH, known for its research and production of automotive … Read more
Hello everyone, welcome to<span>LiXin Embedded</span>. In embedded development, whether it is sensors, memory chips, or GPIO expansion modules, the presence of I2C can be seen everywhere. In this article, we will start from the basic working principles of I2C and delve into common issues and their debugging methods. Why Choose I2C The I2C bus is … Read more