Questions tagged [usart]

USART stands for Universal Synchronous/Asynchronous Receiver/Transmitter is a modern IC which comes with a [UART](https://stackoverflow.com/tags/uart/info) that can also communicate synchronously. A USART is usually an individual (or part of an) integrated circuit used for serial communications over a computer or peripheral device serial port. The tag usart can be used for programming related questions of any usart device.

A Universal Synchronous/Asynchronous Receiver/Transmitter, abbreviated USART, is a piece of computer hardware that translates data between parallel and serial forms. USARTs are commonly used in conjunction with communication standards such as EIA, RS-232, RS-422 or RS-485. The universal designation indicates that the data format and transmission speeds are configurable.

A USART is usually an individual (or part of an) integrated circuit used for serial communications over a computer or peripheral device serial port. USARTs are now commonly included in microcontrollers. A dual UART, or DUART, combines two UARTs into a single chip. Many modern ICs now come with a UART that can also communicate synchronously; these devices are called USARTs (Universal Synchronous/Asynchronous Receiver/Transmitter).

The tag can be used for questions related to programming of a usart device, please note that https://electronics.stackexchange.com/ is another stackexchange website from where you can get answers for electronics related problems. Questions on Stackoverflow should be programming related.

See also tag .

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getcUSART not working as intended? (PIC18F with bluetooth)

I am working on a project with C18 compiler and PIC18F4520. I am having trouble using getcUSART. When I send characters over bluetooth module, at one point it would just hang. int input(char Arr[]) { Delay10KTCYx(400); // Delay between data…
Briget
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AVR Atmega32a USART library isn't working

/* RC_Car_AVR.c Created: 4/18/2018 7:55:07 PM Author : */ #define F_CPU 16000000 #define BAUD 9600 #define TUBRR (((F_CPU / 16) / BAUD) - 1) #include #include char Read; void USART_Init(void){ UBRRL = TUBRR; UCSRB =…
homunculus
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USART receiving nonsense (STM32F0)

I have an implementation for USART communication from a GPS module to a STM32F091 microcontroller. For some reason I only receive nonsense. I have already tried setting different Baud Rates, but none gave me a proper result. Now I am unsure if maybe…
Kater
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USART crashes on PIC18F2550, What can I do?

I'm working in the communication of a PIC18F4550 and the PC with a pair of xBEE S2C. And I am using xc8 to compile the code. I send some characters to the PIC from the PC with an Xbee then I send a '/r', and the PIC has to return me the characters…
D.Martinez
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UART connection between STM32 and Raspberry Pi 3

i'm trying to establish an UART connection between STM32F4 and Raspberry Pi 3 to send motion sensor data. STM32 C code: /* Includes ------------------------------------------------------------------*/ #include "stm32f4_discovery.h" /* Private…
AndrejH
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Determine size of UART software input buffer on microblaze soft-cpu

I need to know the size of the USART input buffer on a Microblaze uclinux. I can access a very reduced BusyBox v1.23.2 I don't know if the buffer is implemented in HW (FPGA), SW or both but I can receive more than 20 Bytes in one non-blocking read…
Stefatronik
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STM32 UART/USART receive issue(without interrupt)

I am trying to transmit and receive data via UART/USART on stm32L476 discovery board to terminal on PC. I am able to transmit the data to PC, but I am not able to receive any. My code is as follows: /* Includes…
user8398475
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What is the USART digital logic in AVR microcontrollers?

Just reading about USART connection in AVR microcontrollers and i faced this question: What is the digital logic used in USART(RXC, TXC and other internals) of the AVR microcontrollers? I've found the answer to this question in the datasheet of…
hexpheus
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What happens in rs232 if both sender and receiver are following odd parity and bit gets swapped?

I am studying USART, with the help of rs232 and max232 for communication. I want to know if, in a scenario, sender and receiver are following odd parity and except the parity and start, stop bit rest bits gets swapped. So in this case how the…
ams
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USART giving unknown values on the atmega 328p

I have been unable to solve a simple USART transmit/receive program. The problem is that I used this in the past and worked effortlessly but now it returns in my Linux machine question marks and in windows some boxes and Chinese characters. I don´t…
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STM32F4 - USART - Receive data array - reads only first frame

today I'm fighting with controlling my uC from the PC. On a button click, I'm sending data to uC which is to change some values in the program. First of all, the problem is that my program reads only first frame received. Secondly, my program gets…
Jejh
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QEMU: USART communication between two MCUs (STM32)

I try to create two qemu instances and let them communicate via usart. the background is, that I want to emulate the communication while the boards aren't even finished but the code is already testable. So the creating of two parallel qemu instances…
Tojan
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Atmega16 USART initialization

I can't for the life of me find why this code is not working to send a byte to my computer terminal window. It receives and works fine when I omit that line though. Receiving and sending also work seperately. Please note that this is over rs485 so…
edagres
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Receiving AT commands

I'm using a microcontroller to communicate with a SIM808 module and I want to send and receive AT commands. The problem right now is that for some commands I receive only some portions of the answers I should receive, but for some others I receive…
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Device not responding to UART commands

I am using an Arduino mega2560 and an EZO EC(Electrical Conductivity) and am trying to send a command using the Serial.print() function. I am using the Arduino IDE 1.6.7. I have some code that seems to work fine which I found online. But I want to…
John B.
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