Stm32 ttl uart. REGISTER based Tutorials; STM32 TouchGFX; .

Stm32 ttl uart Browse in STM32 MCUs Embedded software 2025-04-16; Bug or ill advised design choice: converting between pairs of . Since I am not able to load program to the controller through ST-LINK V2 programmer, so not able debug the code. Note that both the HC-05 Bluetooth module and our STM32 microcontroller are 3. You’ve successfully set up and programmed your STM32 Blue Pill using the Arduino IDE and the DSD TECH SH-U09C5 USB to TTL converter. 9k次，点赞32次，收藏32次。一般stm32f407芯片都会自带好几路uart串口，但从407芯片端口输出的串口uart信号为ttl信号，这时我们就需要485驱动芯片，也可以说是电平转换芯片，将ttl信号转换为所需要的485信号，一般市场上所卖的板子都带这一功能的，因此要实现串口rs485通讯功能，需准备 To start, you’ll need to connect your STM32 Blue Pill to your computer using the DSD TECH SH-U09C5 USB to TTL converter. We’ll only discuss both the TTL-level UART and RS-232 in this sub-section of our tutorial. Being in Bootloader mode means this device is ready to be programmed through USB or UART, flashing firmware into the program memory area, without needing an ST-Link hardware module. However, you may have noticed that Blue Pill STM32 microcontroller does not have an onboard ST-Link debugger therefore we will need a USB-TTL converter. You’ll learn how to use and configure the STM32 UART To Send/Receive Serial Data in polling, interrupt, and DMA modes. Programming the UART1 peripheral in STM32F1 controller for bi-directional communication. We will use F103 and F446, which are connected via two RS485 modules. If the device you refer to is also TTL serial then yes they may well work if connected together (if the device you mention is RS232 then no it won't work). The receiving and transmitting UART must be configured to receive the same data packages. Guidelines For Designing Our HC-05 Bluetooth Driver (Library) Some line driver ICs have internal pull-up resistors on their TTL/LVTTL-side input pins to prevent this and produce an RS232 idle state. Use this function in order to use the print function it's act the same like Printf. We also programmed the STM32 development board to blink an LED. No extra voltage divider resistors are needed or anything else. STM32单片机开发入门(六) 2. Coding . Clone/download this repo. h and a monolith strips user code. However, we are more interested in the TTL-Level supported by the microcontrollers which we’re aiming to (program) drive hereafter in this tutorial. In this tutorial, we’ll learn how to use the Python Serial library to setup For using RS-485 module with microcontrollers a module called 5V MAX485 TTL to RS485 which is based on Maxim MAX485 IC is needed as it allows serial communication over long distance of 1200 meters and it is bidirectional and The Arduino UNO and STM32 boards are widely used boards for rapid prototyping and we have done many useful Step 1: Connect the STM32 Blue Pill to the USB to TTL Converter. 6w次，点赞16次，收藏91次。本文详细介绍了如何使用usb转ttl线实现stm32单片机与电脑之间的串口通信，包括选购合适的usb转ttl线、安装驱动、连接线路及编写测试程序等步骤。 文章浏览阅读1. Hi, I want to control my stm32 with my computer and I want to use UART communication, I use CH340 to convert my ttl signal to USB signal, I want to make supervisory system to control my stm, I can't figure out how do the supervisory system. To send data in half-duplex mode with STM32 UART, you need first to enable TX using the HAL_HalfDuplex_EnableTransmitter function. 3V TTL level. STM32 & HC-05 Bluetooth Module Connection Diagram. Without further ado, let’s get right into it! Table of Contents. The USB-TO-TTL-FT232 is a UART serial module that converts a USB interface to TTL level. It is easy to use, along with features like fast data rate, low power consumption, high stability, suits applications such as safety & security, IoT, and so on. 0V. Blue Pill STM32 consists of three UART modules: UART1, UART2, and UART3. 70€ a 2€ I am using STM32F103(Bluepill). One is through UART. Two of the previous blogs discussed the process of programming your BluePill (stm32F103C8T6) via ST-Link and via UART. VDD to 5V of USB to ttl. 文章浏览阅读5. En esta primera entrada vamos a programar el STM32 por UART, por lo que vamos a necesitar un conversor USB-TTL. 文章浏览阅读6. Interrupts Mode. while using in stm32cubeprogrammer it is working in bootloader mode. 3V, so we have to make sure that our TTL converter operates at 3. 3v的ttl 信号了。如果是通讯，还存在干扰和串扰的问题，走线尽可能短粗是关键。 However, if the baud rates differ between both UARTs they must only differ by 10%. Search for DM00105823 on www. If you can risk working without electrical isolation you might also consider buying a Nucleo-64 board (or something similar), cut off the Embedded ST-LINK/V2-1 from the Cuttable PCB and use this for How To Send Data With STM32 UART Half-Duplex. 0 The difference is that when you connect TTL to TTL, its operating at 3. I have tried the same technique for stm32l073 microcontroller. but while using doclight or herculus the stm32 is not responding to the commands. UART is a communication protocol that enables the user to send data asynchronously through transmit (Tx) and receive (Rx) lines. When I connect the TTL to the USB cable to the PC it appears as a USB-Serial-Controller, UART communication between OpenMV board and STM32 Nucleo board in STM32 MCUs Products I am using STM32L1 Series Discovery board and want to do uART communication via same UART port that is Used for Embedded ST Link V2. connections: STM32 PA9 (TX) to RX of USB to ttl. 6k次，点赞8次，收藏52次。STM32利用STM32CUBEMX快速实现USB虚拟串口回环测试目录STM32利用STM32CUBEMX快速实现USB虚拟串口回环测试1、配置时钟2、开启USB3、开启USB设备：虚拟串口4、生成工程5、修改代码实现回环收发数据测试环境：STM32F103RBSTM32CUBEIDE1. UART3 is available Uart 接口的详细解释. HOME; STM32. Embedded ST Link uses USART1 of STM32L100CT6 and Mini USB is connected to my PC. Currently, it uses UART3, which is connected to the ST-LINK. So, to program the STM32 via UART, you have to enter into Bootloader mode, send the right commands via UART, and then send the program binary. 文章浏览阅读3. pdfMusic: Heroes Tonight Remove the USB-TTL converter from the STM32 Blue Pill and plug the Blue Pill using the USB port. This saves a Overview. STM32F1 Blue pill is a versatile board and can be In this tutorial, we will cover the STM32 USART peripheral. We’ll implement three STM32 UART Receive Examples Using Polling, Interrupt, and DMA to practice what we’ll learn in this tutorial. But there was one huge drawback with it because of the method we used to upload the code. 3V microcontroller UART port, Mastering STM32. 1. However, I use a Such as: TTL level UART, RS-232, RS-422, RS-485, etc. " FT = 5V tolerant pad. c/. , all of them are serial communication. 3V 또는 5V 로 동작한다. The following example picture has its LED on pin PC13. 3V. UART1 is available on pins PA9 and PA10. M0 series 32-bit ARM processor, fast speed, high efficiency; 10/100M Auto-MDI/MDIX ethernet interface, regardless of cross-over or straight-through cable 3. 2 UART输出 TTL电平及转换模块介绍, 视频播放量 3194、弹幕量 20、点赞数 62、投硬币枚数 39、收藏人数 73、转发人数 7, 视频作者 Pulf_bili, 作者简介 闻道百，以为莫己若者，言吾矣。 不做“专 In our previous tutorial, we learned the basics of the STM32 Development Board. Wiring Setup: RXD (SH-U09C5) -> PA9 (RX on Blue Pill) TXD (SH-U09C5) -> PA10 (TX on Blue Pill) GND (SH-U09C5) -> GND In this first post we are going to program the STM32 via UART, so we will need a USB-TTL converter. In this case, it would be more convenient to simply use the built-in USB port of your BluePill for programming. I successfully booted the STM32 via UART and connected it using the STM32CubeProgrammer, following the bootloader configuration document provided by ST You could use the STM32 UART interrupts mode for solving the issue. We will also cover how to handle UART protocol in STM32 and create an example project in interrupt mode using the STM32 NUCLEO-F446RE development board that stm32微控制器提供了多个uart接口，用于实现异步串行通信。uart接口通常用于与计算机、传感器、无线模块等设备进行通信。stm32的uart接口支持标准的异步通信协议，包括数据位长度、停止位、奇偶校验位等配置。 文章浏览阅读3k次。本文详细介绍了stm32的串口配置，包括stm32f103c8t6和stm32f401ccu6的串口分配，并讲解了串口中断模式，如txe、rxne、tc等中断源和待处理位。还讨论了串口通信编程中的常见问题，如缓冲区溢出、非请求响应和响应等待时间，提出了解决方案。 Trong bài này mình sẽ hướng dẫn và giúp các bạn giao tiếp UART với máy tính 1 cách đơn giản và nhanh nhất. 11、配置时钟2、开启USB3、开启USB设备 The 2-CH UART TO ETH provides an easy way to communicate between UART TTL and RJ45 Ethernet, allowing bi-directional transparent data transmission. With more than 600 microcontrollers, 속칭 TTL 레벨이라 함은 MCU의 VDD 전압값과 동일하며 MCU 에 따라서 3. st. Jumper cables for connecting; Micro USB cable; STM32 Flash loader demonstrator; USB Maple serial drivers. 0v 的ttl 尚且如此，更不要说3. Features. com. This article shows you In this tutorial, we’ll discuss the STM32 UART Communication. We will use Arduino IDE to program our STM32 Blue Pill using the micro USB port. We’ll also implement a couple of STM32 UART Este guia aprofundado combina conceitos teóricos, configuração prática e técnicas avançadas para dominar a UART no ecossistema STM32. However, you may have noticed that Blue Pill STM32 The 2-CH UART TO ETH provides an easy way to communicate between UART TTL and RJ45 Ethernet, allowing bi-directional transparent data transmission. UART Flow Control is a method for slow and fast devices to communicate with each other over UART without the risk of losing data. 20 on Aliexpress. 3V and nextion works "If the 5V UART interface input is TTL compatible, VOL<0. 3v TTL levels. We also learned how to find a serial port name on Linux, Windows, macOS, and Raspberry Pi (RPi). An STM32 FT pad can accept 0V to 5V CMOS level input when VDD=3. This question uses the STM32H723 So I am transmitting data at 7MB/s over UART to a PC. However, there may be times you don’t carry around a ST-Link or a USB-to-UART Converter. 2. ESP32 provides three universal asynchronous receivers and transmitter (UART) ports such as UART0, UART1, and UART2 that work at 3. 8w次，点赞591次，收藏1. Send data from UART to UI; STM32 Communication using HC-05; Subscribe. 0 4- Platformio IDE 5- STM32 CUBE Programmer software which detects and connects to my board through UART. We can use any UART module for serial data transmission. Estos conversores USB a TTL son dispositivos baratos, y muy útiles, que podemos encontrar en AliExpress o eBay por entre 0. 开启debug2. in STM32CubeMX (MCUs) 2025-04-14; Also, the UART can be used with interrupt. If you wire them direct check that the STM32 UART rx pin is 5 volt tolerent (most are) if the deveice toy mention is 5 volt TTL. STM32 PA10 (RX) to TX of USB to ttl. It is easy to use, along with features like fast data rate, STM32. a dedicated configuration tool is provided by ST: STM32 you can directly connect a “USB to Serial TTL” type FTDI cable in 3 usb 转 ttl 串口模块是一个非常实用的工具，可以测试模块的 uart 串口通信和通过单片机的 uart 接口给单片机等下载程序。 能够在电脑上的串口助手软件非常直观的显示出串口设备返回的数据以及发送相应的控制数据给串口设 RS232串口经常用到，本文分享下RS232协议方面基本点，并介绍一种简单的串口TTL（3. For reliability use TTL(3. Then, you can send the data you want to send over UART in half-duplex mode, and switch back to the RX (receiver) mode to capture any incoming data. STM32에서 UART 동작은 다른 주변장치와 같이 Polling 방식, 인터럽트 방식, This tutorial is the start of a new series on the UART peripheral of STM32 Microcontrollers. Display and stm will connect via to uart(Rx Tx pins). Echo characters received from UART and transmit time elapsed since boot every 5 seconds. TTL TX -> STM32 USART1 RX (PA10) TTL RX -> STM32 USART1 TX (PA9) After this setup, I sent the 0x7F command to initiate communication but did not receive any response. Proper bootloader; To get the proper bootloader for your Blue Pill, read the pin number for the built-in LED of the board. Objectives. This converter will allow your computer to communicate with the STM32 Blue Pill via its UART interface. It is easy to use, along with features like fast data rate, low power consumption, If you want to interface TTL-level UART signals to the STM32, you can connect them directly to the STM32's UART RX and TX pins. R is a slower device than T, and R cannot keep up. 0 to TTL UART Module Serial Converter CP2102 Replace Ft232 Adapter Module for $1. Stm work with 3. This is a typical example on how to use the STM32F1xx USB Device peripheral where the STM32 MCU behaves as a USB-to-RS232 bridge following the Virtual COM Port (VCP) The UART instance and associated resources (GPIO, NVIC) can be tailored in "usbd_cdc_interface. We will use STM32CubeIDE to create a project where we will use UART interrupt of STM32 Nucleo to receive data on 1. org/assets/pdf/boards/original-schematic-STM32F103C8T6-Blue_Pill. 3V，电路如下图 UART is a communication protocol that enables the user to send data asynchronously through transmit (Tx) and receive (Rx) lines. Consider the case where two units are communicating over UART. 3 Volt digital, there are possibility of wrong data due to noise. 8V and VOH>2. We utilized an FTDI programmer/ USB-TTL Converter module for programming. I want to do UART by connecting USB to TTL converter(PN-USBTTL-FT, FTDI FT232RL) to Tx and Rx of the board pin without using the USB port of the. Learn how to set up UART and stm32f103的pa9连接到usb转ttl模块的rxd。 stm32f103的pa10连接到usb转ttl模块的txd。 gnd连接到共同地线。 配置uart外设. 70€ to 2€. 5. meaning that It has no problem connecting but there are issue with setting up the Platformio In the previous tutorial, we discussed the universal asynchronous receiver-transmitter (UART) protocol and voltage levels, covering USB-serial boards and other serial adaptors. USB to Serial/USB to TTL adapter. STM32定时器包含基本定时器、通用定时器和高级定时器，其中TIM6和TIM7是STM32当中的基本定时器，作为初学者，先从最基本的学起最容易，下面我们 前期知识 关于TTL电平 TTL是Transistor-Transistor Logic，即晶体管-晶体管逻辑的简称，它是计算机处理器控制 STM32 HC-05 Bluetooth Module Interfacing . Conectar el STM32 conversor USB-TTL. PA9 Pin as USART1_Tx of STM31L100CT6 PA10 Pin as USART1_Rx of STM31L100CT6 In this tutorial, we’ll discuss the STM32 UART Interrupt DMA Polling methods using the HAL APIs. In this article, we discussed what are the STM32 Boot Modes and how they are implemented on the STM32F030x series, what’s a Bootloader and how to use STM32CubeProgrammer to flash an STM32 using UART. So - just set device into boot mode (by setting BOOT0 and BOOT1 In this tutorial, we will discuss how we can interface STM32 (as master) to any RS485 (Modbus RTU) based sensor (as slave) using STM32Cube IDE. Onboard ttl是电平信号，经过传输线后有压降。问题来了，高电平的数字信号1就可能在接收侧落入不定区或直接降为低电平的数字信号0。5. Refer following fig. 2k次。博主能力有限，有错误望大佬指出 0x00 文章内容：UART阻塞方式收发UART中断方式收发UART中断回调函数UART DMA方式收发printf()函数串口重定向0x01 UART阻塞方式收发CubeMX or CubeIDE配置1. # STM32系列-串口-uart-引脚上拉-原因问题的搜寻前言-（知道一个结论正确，也要知道它为什么正确）问题描述查找过程（1）上网查资料（2）请教大佬（3）查代码-找手册 1、当TTL电路驱S电路时，如果TTL电路输出的高电平低S电路的最低高电平（一般为 The user manual for STM32 Nucleo-64 boards might be an interesting starting point for you to find an answer. Don't have ST-Link? No worries, use FTDI or any USB-TTL Converter to uploadUse STM32 Cube Cube Programmer UARTFTDI driver is here https://ftdichip. One of the serial communication methods is UART, the word UART stands for Universal Asynchronous but you must use a TTL to USB STM32单片机开发中，USB转TTL模块通常用于数据传输。开发人员可以利用USB转TTL模块来与嵌入式设备进行通信，以验证设备功能和传输数据。_usb转ttl. REGISTER based Tutorials; STM32 TouchGFX; Riverdi STM32 Display #3. Set the configuration bits to match Flow Control in UART. I am loading the program through UART(USB-TTL) I want to know if there is a way to debug the code using UART(USB-TTL), i want to analyze the real time me USB to TTL Serial PL2303HX sử dụng IC chuyển đổi USB to COM PL2303HX với nhiều cải tiến về hiệu năng của hãng Prolific. . We will create an example project by interfacing a RS485 Modbus protocol based WS-TTL-CAN is a TTL UART to CAN module which is compact and easy to integrate, onboard high-performance MCU, with TTL and CAN conversion protocol, easily achieving UART to CAN via simple configuration. These USB to TTL converters are cheap and very useful devices that we can find on AliExpress or eBay for between 0. Luckily, the STM32CubeProgrammer knows which commands to send to the STM32 through UART, so you don’t have to worry about it. Eventually, the Bootloader will program your binary into the main Flash memory. Additionally, you also need to install the STM32 plugin. 使用外部晶振 如果你的板子上没有晶振的话，就不要开了，不然stm32 By two methods we can upload Arduino code onto stm32 blue pill. A transmitter T is sending a long stream of bytes to a receiver R. STM32 UART Interrupt, DMA, Polling (Receive Modes) There is no need to program the device with any firmware - the UART is used for direct communication with device through embedded bootloader. 在主程序中初始化uart并实现数据发送 Step 1: Connect the STM32 Blue Pill to the USB to TTL Converter. Case in point: 6Pin USB 2. UART (Universal synchronous asynchronous receiver transmitter ) là một ngoại vi cơ 文章浏览阅读2. For a better overview of the topic, let’s list down all the other possible ways to receive/transmit serial UART data with an STM32 microcontroller. com/drivers/ UART (Universal Asynchronous Receiver/Transmitter 通用异步接发器)：是串口通信的物理接口，可以独立成芯片或是作为模块嵌入到其他芯片中。 TTL串口 、 RS-232 、 RS485 都是串口通信协议，区别在逻辑电平表示方式不同。在arduino、STM32等单片机内所使用的都是TTL串口。 STM32L0 Arm Cortex multiplexing UART and SWD. h" header file according to your hardware configuration. This article shows you Overview Introduction. GND to GND of of USB Overview The 2-CH UART TO ETH provides an easy way to communicate between UART TTL and RJ45 Ethernet, allowing bi-directional transparent data transmission. The supply voltage of the STM32 is 3. If you have RS-232 level signals you will need an RS-232<->TTL interface, like a MAX232, STM32 UART Receive/Transmit (Rx/Tx) This tutorial is intended to be an example application for STM32 UART DMA Rx/Tx operations. Otherwise, a pull-up resistor can be added. UART2 is available on pins PA2 and PA3. There are products that can directly connect an USB ports to a 3. 7 volts, logical 1 is between 2 and 5 volts. There are a total of 3 UART ports. If you have some issues doing so, you can always refer to the previous tutorial using the link below. 50/1 on but the hardware is cheaper. Setting up Arduino IDE for STM32. In this series we will cover different ways of transmitting and receiving data over the UART protocol. A pull-up resistor on the UART serial Receive Data (RXD) input pin is not necessary because the RS232 line receiver is always driving that pin. 3V) to UART level shifter at both ends. This STM32 ARM microcontroller can be in Bootloader or Normal Operating Mode. With this converter, a computer or other device with a USB interface can connect to TTL logic level devices, such as microcontrollers, sensors, and usb转ttl模块1. Thus, you should have the latest version of Arduino IDE. Giới thiệu về UART. 为什么要再次制作usb转ttl模块我思考了一下，总结以下两点说明为什么要再做usb转ttl模块之前用ch340做过一款usb转ttl的模块，但是有瑕疵，主要是输出引脚的丝印没有添加时间长了，只有一个在用，其它都不知道丢哪去了手上有其它同等功能的芯片，于是就决 Triple USB-to-serial adapter using STM32 blue pill (pill_serial) by snm, USB UART IC], specifically for interfacing USB to serial. TTL-Level UART stm32的uart硬件电路，在进行线接传输时，一般低于230400bps的波特率 如果要实现接线方式的串口信号传输距离加长，常用的方式为采用rs232电平转换芯片，将uart的ttl电平转换为rs232电平，但因为rs232标准依然是单端信号标准，所以也不能有效提高 First Add use UART Handler and its init in this function i used UART2 change it to your periph if you use Stm32 Cube or IDE just select the periph it is automatically generated. Open the MPLAB IDE and create a new project name it “PC_Control_USB-TTL”. ESP32 UART Pins. 3V）电平转换为RS232电平的电路，这个电路是经过制板验证过的。使用芯片MAX3232E （tssop16封装），电源用3. To start, you’ll need to connect your STM32 Blue Pill to your computer using the DSD TECH SH-U09C5 USB to TTL converter. I guess that the convertor between UART and USB in this case is implemented in an ST-Link utility embedded on standard Nucleo Boards. The UART TO ETH module provides an easy way to communicate between UART and Ethernet, it can be configured via web page. Module USB to TTL Serial PL2303HX có sẵn các thành phần cần thiết, bạn chỉ cần cắm vào cổng USB của máy tính là có ngay 1 cổng COM ở mức 5V có thể giao tiếp với vi điều khiển. 我面试的时候一般喜欢问应聘者一个问题： UART 与 RS232/RS485 的区别与联系？ 很多人对于这个问题答得都不是很好。还有些人压根就没有想过这个问题，一直认为他们是同一个东西，就是咱们俗称 Schematic: https://stm32-base. You have a signal when UART is done with the transmission or reception and ready for service. This powerful microcontroller opens up a world of possibilities for your projects, offering the performance of a 32-bit ARM Cortex-M3 processor at an affordable price. store_____ 1- MacOs Catalina 2- STM32103c8T bulepill board 3- SLAB UART USB-TTL CP2012 V3. Check if there is any difference in Ground potential between both boards using a mutimeter. It involves a shared baud rate between the transmitter and receiver. 选择“UART In this video I will show you Stm32 programming using USB to TTL ConverterIf you found this video helpful give a thumps up If any suggestions do let me know How to interface the RS485 to TTL converter module with STM32. In that mode, you don’t have to wait to finish the data transmission. Before diving into programming your BluePill, it’s better to know its operating modes. We will also see different UART In this tutorial, we will show you how to use STM32 Nucleo UART in interrupt mode to transmit and receive data. 3V CMOS output can drive without any problem. This converter will allow your In this tutorial you will learn how to establish a serial communication between STM32 STM32F103C8 and Arduino with examples and code RS232, RS485, I2C, SPI, etc. This implies that a 3. UART接口：通用异步收发器（Universal Asynchronous Receiver/Transmitter)，UART是串口收发的逻辑电路，这部分可以独立成芯片，也可_串口ttl是线序 STM32串口TTL和RS-232 文章浏览阅读10w+次，点赞52次，收藏391次。注：串口发送数据(usart)是stm32调试中经常使用的功能，但是电脑usb的电平标准与串口所使用的ttl标准不同，所以需要一条usb转ttl线来完成它们之间的通信。本文介绍使用usb转ttl线完 Purchase the Products shown in this video from :: https://controllerstech. This article goes through the following UART features: Simple UART communication in polling mode; UART with Interrupt ; UART with DMA ; 2. The sample demo we provide is based on STM32F103RBT6, The STM32 UART is TTL, not ''TTL inverted''. 6w次，点赞17次，收藏63次。关于stm32的uart口是否需要接上拉电阻我主要是在《电路设计与制作实用教程----基于立创eda》里面看到stm32的uart口还接了个上拉电阻，我不是很理解。我去看了下正点原子的 对于TTL电平的UART，起始位为低电平，停止位为高电平，发送的数据是从bit0 - bit7，空闲时为高电平。 2. The chip is about $4. 使用stm32cubemx配置uart2为通信模式。 设置波特率为9600，数据位为8位，无校验位，1个停止位。 编写代码. Open in app. STM32 Blue Pill UART Ports. Notify of 具有usb接口和uart接口的stm32芯片，如stm32f1, stm32f4等等，都可以实现usb转ttl串口工具的制作。目前具有usb接口的最小资源的芯片是stm32f103c6t6。这里介绍usb转uart的代码设计。stm32例化的usb vcom，数据通讯到stm32内部设定的缓存空间，如果不向外部进行uart转发，则vcom的波特率为名义上的波特率，实际上是 STM32 Microcontrollers use TTL-like signaling, where logical 0 is between approximately 0 and 0. 485总线有上拉 电 阻R40和下拉 电 阻R45分别上拉到 电 源和地，因此总线默认Ua &gt; Ub，对应逻辑为1TXDE Considering STM32 Nucleo Boards, implementing a communication by serial port with a computer is a matter of using UART on the Nucleo Board and connecting it to the computer via USB, where you emulate serial with PuTTY. mbpu fvdr zjqry geklu bndila xakidg ybldz fqung ceas fbrhk aawgzz rqdew ljsosnzj fcghjsn zqtn