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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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Cross-thread operation not valid: Control 'textBox1' accessed from a thread other than the thread it was created on

I want to send temperature value from a microcontroller using UART to C# interface and Display temperature on Label.Content. Here is my microcontroller code: while(1) { key_scan(); // get value of temp if (Usart_Data_Ready()) { …
Fatima Zohra
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What is the difference between baud rate and bit rate?

I am really having hard time understanding the difference. Some say they are same, while others say there is a slight difference. What's the difference, exactly? I would like it if you explained with some analogy.
dimSutar
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UART vs I2C vs SPI for inter-processor communication between microcontrollers

I am examining a way to connect two microcontrollers. On the level of serialization I am thinking of using Nano protobuffers (http://code.google.com/p/nanopb/). This way I can encode/decode messages and send them between two processors. Basically,…
Drasko DRASKOVIC
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Device node at /dev/tty* not getting created for uart serial driver

I have written a simple UART serial driver in embedded Linux running busybox with mdev rules. I have provided .dev_name as "ttyC2C" in my driver code. static struct uart_driver serial_omap_reg = { .owner = THIS_MODULE, .driver_name =…
manav m-n
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GATT profile and UART service

I am new to developing a mobile app with bluetooth connection to peripheral device. I searched that GATT is the relevant profile used for bluetoothLE communication but our client recommended that we use UART service. Now I am confused as to 1. how…
Samra
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is it possible write to console without stdlibs? c/c++

I am programming on an arm microprocessor and am trying to debug using print statements via UART. I do not want to add stdlibs just for debugging. Is there a way to print to the console without stdio.h/iostream.h ? Is it possible for me to write my…
Sam
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ARM: reading modbus data through UART fails

I am trying to read a register from an RS485 adapter using a UART connection on an ARM board with no success Machines ARM board: CM-T335 - TI AM335x Computer-on-Module http://www.compulab.co.il/products/computer-on-modules/cm-t335/ PC: x86 machine…
Taher
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Why is my buffer length ignored?

I'm developing a receiver for a small hardware project. I'm working on a small board that uses UART to transfer data. The receiver code is shown in full below, I'll explain the problematic bits separately shortly. #define TTY…
Etheryte
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Configure minicom to use hardware flow control

Looking for some assistance testing a UART implementation with hardware flow contorl for the OMAP L138. To test the implementation I use minicom to emulate the other end of the serial link and I'm looking for some insight into how it needs to be…
dinesh
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STM32: Implementing UART in DMA mode

I am trying to implement UART in DMA mode to transmit a simple string every time a push button is pressed. So I have used CubeMX to generate the code and I have configured UART2 TX DMA in normal (not circular) mode and also no FIFO and no…
Nixmd
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Raspberry Pi UART serial wont work

I am trying to send/receive data over serial connection (GPIO UART pins) between a Raspberry Pi (B model, raspian wheezy) and an STM32F4 board. To setup the serial port, i followed all the stepts found in several tutorials like:…
Martin Law
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Qemu baremetal emulation - how to view UART output?

Question: How do I get the UART output from a baremetal program run with Qemu? Background Here is the command line invocation I have been using: qemu-system-arm -M xilinx-zynq-a9 -cpu cortex-a9 -nographic -kernel $BUILD_DIR/mm.elf -m 512M -s…
thatjames
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QEMU MIPS32 - 16550 Uart Implementation on a Custom Board

I’m trying to use QEMU to emulate a piece of firmware, but I’m having trouble getting the UART device to properly update the Line Status Register and display the input character. Details: Target device: Qualcomm QCA9533 (Documentation here if…
SwarthyMantooth
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IOError: [Errno 2] No such file or directory (when it really exist) Python

I'm working on transfer folder of files via uart in python. Below you see simple function, but there is a problem because I get error like in title : IOError: [Errno 2] No such file or directory: '1.jpg' where 1.jpg is one of the files in test…
user8207105
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iPad accessory communication through UART

We manufacture a new accessory for iPad/iPhone which should transfer commands to the iPad. We like to use UART (through a certain Apple-protocol called Lingo). My research shows that I can only use USB (30PIN Connector) and custom…
Sebastian Roth
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