Questions tagged [uart]
A UART (Universal Asynchronous Receiver Transmitter) is a piece of logic that sends and receives data on a serial port.
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In AVR-GCC, I am trying to get an atmega328p to sleep and then wake on USART RX, but it locks up
My hardware is pretty straight forward. I have an ATMEGA328P hooked up with an LED on PB5, primarily to troubleshoot, and a wire that connects PD2 (INT0) to PD0 (RX), hoping to use INT0 to wake up the ...
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CH32V003 MCU max USART baud rate
I will work with the CH32V003A4M6 microcontroller and must configure its USART for serial communication.
My application needs to go up to 460800 baud rate.
Does someone know if this is possible, or ...
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Problem in detecting the line feed character in inter-micro UART communication [closed]
Setup:
There are two MCUs, communicating with each other over UART. Let's call the transmitting MCU as A, and receiving MCU as B. MCU A and B are different. A is SAML22 (using IAR Compiler) and B is ...
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STLink v3 serial doesn't work
I'm trying without any success to get STLINK-V3MINIE serial to work. It shows up as a serial port on the laptop:
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Do FT232 come pre-programmed out of the package?
I'm working on a board which requires USB serial communication. For this I want to use an FT232RNL, however I'd like to know if I need to program it before I install it on the board. Also, do I need ...
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LED does not blink when transmitting/receiving UART
I constructed the circuit as shown in the picture (I omitted the unnecessary parts)
I expected the LED to blink when the UART transmits and receives, but the LED is always on.
Is something wrong with ...
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Efficient Padding for UART to Minimize Power Consumption
So, I am implementing a custom protocol over UART (data field in the packet is fixed at 8 bytes + contains a len field). If the data len is less than 8 bytes, 0xFF is being used for padding. I ...
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Communication does not occur when connecting an LED to the UART line
I attached LEDs using transistors to UART RX and TX as shown in the attached photo.
But the led doesn't work and the uart doesn't work either.
If I remove this circuit the uart works fine
What's the ...
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FT230X using USB-C receptacle not working for data transfer
I have tried to add a USB-C connection to my PCBA solely for data transfer.
I have used a FT230XQ-R microchip (Datasheet) and followed their uploaded example for a USB-C receptacle. I have now ...
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FTDI chip not working properly [closed]
I recently purchased an FTDI chip from AliExpress. However, every time I try to use it on Linux via the picocom command, it gives me a lot of unknown characters. I ...
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How to work with UART to make communication between stm32 and hmi nextion display in noisy environment?
in an ultrasonic generator project, I am using an STM32F334 microcontroller as the main controller and an HMI Nextion display (model NX8048T070) that includes another STM32 for driving the monitor. I ...
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Is it normal to get garbage output through UART when resetting the microcontroller?
I have written functioning code for Serial Communication through UART, and when stepping through the code it transmits characters just fine. I have done this using microlib, so I can use printf (I ...
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What is the real transmission speed in UART?
I'm trying to transmit data at 6.144 Mbit/s through the UART port of Nucleo-H723ZG microcontroller. For reading on the PC, I'm using Free Device Monitoring Studio. Based on my UART parameters, I ...
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Decoding unknown serial data from treadmill console board
I have been working on a treadmill project whereby my aim is to manually control the treadmill with an Srduino without using the remote.
Info about the treadmill - The treadmill is just a normal ...
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Fingerprint sensor module communication (FPM383 R503)
I'm working on a fingerprint sensor that is known as FPM383. It is much like the well known R503 sensor. Their datasheet and serial communication manual are almost identical.
I was trying to control ...
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For a UART communication, when do we enable/disable the peripheral wrt changing between transmitting and receiving mode?
I am working with SAML22 microcontroller and I am supposed to write the transmission code using the interrupt mode. I am confused in which case I am supposed to disable the peripheral.
When changing ...
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UART communications using CAN bus differential signalling
I need to interface with a device that talks UART, but with CAN bus signalling. Here's a picture where a tester (which I want to replicate) talked to that device:
While RS485 seems similar, the ...
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UART between TMC2208 and Ardurino : unable to use read from TMC
LT, DR:
I can program the TMC via UART but can't read anything back, and I don't like it :'(
Description
I want to make my ardurino UNO communique with a TMC2208-V3.0 (manual). The use case is to ...
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UART gets stuck after some time
I'm trying to make UART connection to Atmega328p from HW-199 UART module. Here's my code:
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Why does RS-232 Communication fail between these 3 ESP32's?
What's the Goal?
Trying to get two esp32's to communicate over their UART lines using RS-232.
My initial inspiration and idea for the connections was based on
https://esp32io.com/tutorials/esp32-rs232
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STM32 HAL_UART_RxCpltCallback how to use it properly
I am developing an STM32H750 PCB for a future project and I am doing some tests on an STM32F103 to get familiar with STM32CubeIDE.
I am facing a problem with the ...
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UART GPIO Expanders
I'm looking for a GPIO expander with UART interface, but I can't find a single IC. I know that this is not the place to ask for product recommendations, but I wonder why there are hundreds of GPIO ...
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Using V2DIP1-48?
I am trying send data (in the forms of int or strings) from a Teensy 4.1 via UART to USB (in my case, a Flash Drive). I am using a V2DIP1-48 to receive the data from the Teensy, convert it to UART, ...
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Gibberish data with custom Atmega 2560 UARTs
So I have an issue with the UART configuration of my customized uC based on the ATmega2560.
To establish serial communication, I'm using the FT232RL chip and the Arduino IDE.
I don't have any issues ...
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How to configure STM32 UART TX to generate a decodable signal?
I am trying to transmit data from an STM32F411 (blackpill) via UART, and am having trouble generating a signal that works.
The problem is that, when configured with the default GPIO settings, the UART ...
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Custom Arduino MEGA crashes ONLY on a specific command when plugging UART-USB converter before main power. Phantom power leaking through UARTs pins
Disclaimer
Based on multiple attempts to find the cause of the problem, I have determined that I might be facing a hardware issue rather than a programmatic failure, hence why I am posting this here ...
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A7682E LTE modem parse file downloading with UART
I need to parse the data that SIMCOM A7682E modem is sending to the UART.
It seems simple until I tried to do that. The main problem is that modem does not waiting between data packets. So there is no ...
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Making wired USB MIDI controller transmit data over Bluetooth
I want to make a USB MIDI controller more practical by passing the data via bluetooth. I'm don't have that much experience with electronics engineering, so I'm coming here ask for advice.
Namely it is ...
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Power via UART breaks MCU
I have some modules, each with their own STM32 MCU, connected on the same power supply. These modules are communicating via UART.
When plugging in multiple units I get the problem that modules are ...
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UART only succesfull on first transmit
I have a STM32 NUCLEO-L031K6 board that I am trying to test some UART on.
Following this guide: https://wiki.st.com/stm32mcu/wiki/STM32StepByStep:Step3_Introduction_to_the_UART
I get TeraTerm to show &...
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Use digital sensor with USB to serial TTL converter?
I have a sensor (HC2A-S3A), which provides analog and digital output signals. The digital interface is UART (19200 baud, protocol RoASCII). Can I use a USB to Serial TTL Converter (chipset: FTDI ...
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STM32H7 CortexM4 DMA issue
I'm trying to use USART + RTS only + DMA(non circular, peripheral to memory, DMA1 Stram0) on STM32H755ZIT6's M4 processor.
I and D caches are enabled.
My code is working on M7 but it does not works ...
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Convert RS232 signal to USB
I have an optical amplifier that uses RS232 and I want to convert to USB. I've purchased this chip, also here. There is little documentation on this chip and the supplier hasn't responded to questions....
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STM32 - Implementing UART to USB convertor
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 ...
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STM32F103 UART DMA transmits corrupted data sometimes
I`m using STM32F103CBT6 core with UART via DMA on 9600 baud rate.
The device in idle state transfers data between controller and bill validator unit. In the same time I`m sniffing the data that are ...
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How to reduce on-resistance and parasitic capacitance effects of my MUX setup?
I am designing a mux board to mux a flashing setup. Both UART and SPI lines are on 1.8V logic. The Mux chips have ~4-8ohms on-resistance and 1.7pF on-capacitance. Few questions:
Would I need buffers ...
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PCB Design review for STM32 USB-UART bridge
Could anyone review the schematic for CH340 chip. My goal is to drive STM32F030C8T6 automatically into bootloader mode while uploading code.
Unfortunately I am not able to program this board without ...
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Setting Boot Mode on Microcontroller without Boot Selection Pins
I've been tinkering around with this Generalplus microcontroller: GPM32F0118B and there are datasheets/some materials here: https://www.generalplus.com/GPM32F0118B-MkCri-...
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TX and RX of UART are not connected to the board [closed]
I am looking in a TP-Link router and found an UART port. While I could determine the Volt and Ground ports using a multimeter, I couldn't distinguish between the TX and RX ports (two pin on the right) ...
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Using UART of zigbee chip cc2652p in both ways, programming the chip (via usb to UART) and while operating the chip on raspberry pi
Excuse me if this is a dumb question :)
I am designing a pcb that is to be a hat over a raspberry pi to add zigbee functionality. The hat will use zigbee module cc2652p from texas instruments. The ...
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UART Transmitter implementation using Verilog
I am trying to implement the UART transmitter FSM using Verilog, but the FSM is stuck at IDLE state. Can someone tell what mistakes am I making? The code is as ...
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3m unshielded 3V3 UART
I have a product that probably uses the wrong digital interface, but I'm trying to make it work anyway. Differential signalling, a better cable and other things would be desirable, but that is outside ...
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Low drive strength of level shifter
What part of a level shifter datasheet indicates drive strength?
I have an MCU and sensor connected over UART (115200 baud). The MCU is 3.3V and the sensor is 1.8 V, so I'm using a level shifter in ...
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STM32 UART only works while ST-Link is connected
I'm using an ST-Link broken off from a NUCLEO board to program a custom board with an STM32G4A1 on it. The issue is that UART transmission only seems to work while the ST-Link is connected (verified ...
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STM32 Help receiving serial data sent from python's pyserial
I need some help communicating between python's pyserial and an STM32f030R8 microcontroller. This is for a 2 DOF robot which has a python base GUI. The GUI will send, via serial communication, the ...
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Confusion with polling data by an MCU using UART
I'm using an MCU board(STM32 with HAL) and basically polling data from a device using serial protocol. The MCU sends a fixed byte array(6 bytes) to the device, and in response it receives a fixed byte ...
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Reducing EMI caused by unterminated serial TX line
I have a PCB with a serial TX UART used for programming & logs.
Most of the time nothing is connected & the ~50mm TX trace is unconnected - basically an antenna.
Are there any best practices ...
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Smart Card (SIM Card), connect to stm32 via USART
After get ATR and send PTS, I tried send APDU, but response always the same as APDU which has been sent.
I tried to change the frequency for USART (clock) and baud rate, after I tried to change PTS ...
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Issue with MAX3140 UART when sending 64-bit frame using 16-bit frame configuration
I am facing an issue with the MAX3140 UART when attempting to send a 64-bit frame through a 16-bit frame configuration. The MAX3140 uses a 16-bit frame for communication, where the upper 8 bits are ...
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Why does my opto behave like this?
Can you help me explain why my opto (LTV-817S) is behaving like this?
The schematic is shown below and the scope below that.
We are using an STM32 communicating with an ESP32 via USART at approx 38400 ...
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