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Questions tagged [uart]

A Universal Asynchronous Receiver/Transmitter (UART) is used for serial (where each bit of data is transmitted along the same connection) communications over a computer or peripheral device serial port.

UART is usually an individual (or part of an) integrated circuit used for serial communications over a computer or peripheral device serial port. UARTs are now commonly included in microcontrollers.

Simple serial link via UART uses two lines TxD and RxD, other than ground, for transmit and receive data:

Simple UART connection

It is asynchronous communication. Hence data transfer settings (number of bits, baudrate etc.) should be matched between devices wanting to communicate. The electric signaling levels and methods are handled by a driver circuit external to the UART.

More information:

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Fletcher checksum: Is a modulo-255 sum really the same as a one's complement sum

Short background to my question: I'm working on a small hobby project with a microcontroller communicating with a PC over UART. Right now I'm using COBS byte stuffing with 0x00 packet delimiter bytes and a simple 1-byte checksum that is either a…
Henrik123
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ttyusb/uart sends 'USB' during transfer

I am using Go for a project and am transmitting data to an embedded device via the serial port (ttyusb). During fast and "large" transfers I've noticed that the transmitted data did not match the values I'd wanted to send. I've tried various…
martin
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Unable to export UART channel on Beaglebone

I am trying to program the BeagleBone to communicate with an Arduino over UART. I have my code working flawlessly when I connect via USB, but I need to use the Adafruit BBIO library to access the UART functionality since the USB port is taken in the…
Jordan Lewallen
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UART communication in Gem5 with ARM Bare-metal

I am currently working with Gem5 and I have to access via UART from my Host to ARMv8 bare-metal option, so i tried lots way but i stocked yet. could you please let me know, how can i map my host's Serial port to ARMv8's Serial Port in bare-metal…
Younes Mahboub
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Android Things: Connect to Serial Debug Console

I've been trying to connect to the serial console of a Raspberry Pi 3 with Android Things using USB to TTL cable from my Linux (Ubuntu) machine. Despite I connected the cable as per the documentation, all I get when executing the minicom command is…
Onik
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parsing complete messages from serial port

I am trying to read complete messages from my GPS via serial port. The message I am looking for starts with: 0xB5 0x62 0x02 0x13 So I read from the serial port like so while (running !=0) { int n = read (fd, input_buffer, sizeof input_buffer);…
Ariel Baron
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Linux read() latency

Is there a way to improve latency on serial port data processing in Linux (4.8)? In particular, the time between actual data on the line and when select() and read read() functions on this port return. Right now, my measurement shows 350…
ilya1725
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Arduino + Analog Discovery ( UART )

I'm going crazy to resolve this problem: i need to configure my Analog Discovery to read data sent by PC to Arduino over RX pin. PC and Arduino communicate via UART protocol standard, with 1 start bit, 8 data bits and 1 stop bit. I tried to sample…
Giampaolo Bovenzi
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Redirect multiple UARTs in Qemu

I am emulating a chip with multiple UARTs/USARTs. What I want to do is redirect UART3 to /dev/uart3 on the host, uart7 to /dev/uart7 on the host, etc. I can't seem to find examples or guides that deal with more than one uart, and the examples I did…
Seth
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Write UART on PIC18

I need help with the uart communication I am trying to implement on my Proteus simulation. I use a PIC18f4520 and I want to display on the virtual terminal the values that have been calculated by the microcontroller. Here a snap of my design on…
Daymov
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Set 16550A UART Hardware FIFO interrupt level from Linux Userspace

I am currently using a 16550-compatible UART, and I want to be able to change the FIFO interrupt trigger level (I am dropping bytes under high UART loads and I want to reduce the threshold - it's an underpowered embedded system). Of course, I can…
Damien
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Reading data from different UART drivers

I have a problem due to different UART driver behaviour porting an application from an old ARM-based system to a new one. These are Linux embedded systems, one an Atmel AT91 with kernel 2.6.14 and the other a Freescale iMX6 with 3.14.38. My…
Dan
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How to send boot files over uart

I have a beaglebone black board. A host with 64 bit ubuntu14.04 I wanted to transfer uImage file over uart to beaglebone. So I stopped at u-boot and type U-Boot# loadb ## Ready for binary (kermit) download to 0x80200000 at 115200 bps... Now it is…
almirah almirah
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Linux Reading Data from UART

I want to read data from UART, i followed this tutorial, the write function works as expected, however i'am getting problem with the read function : This is the uart_init function: void uart_init() { printf("\n…
fedi
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PIC18F25K80 sending string through USART not working

I'm programming a few libraries for a board with a PIC18F25K80 built-in. Right now I'm trying to program the UART library and I've tried everything but I cannot make it work when it comes to send a string of chars. I'm using the XC8 compiler and I…
Iker Ramírez Gorostizaga
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