a Universal Asynchronous Receiver/Transmitter, better known as serial port

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3
votes
2answers
33 views

ttyAMA0 disabled but still shows one boot message

I'm trying to use the UART for my own purposes. I'm using Raspbian I've edited cmdline.txt and inittab but I still get the one line message Uncompressing Linux... done, booting the kernel. How ...
2
votes
1answer
40 views

UART cannot send

UART on my pi cannot send data, I can receive data from another machine, but I cannot send any data using the 'tx' pin of UART. I also try to connect 'tx' and 'rx' on my pi, but still no data is sent ...
0
votes
0answers
19 views

PIGPIO: Can child process use the parent initilized pigpio library?

I have a parent process (which is a basic tcp server). This process calls gpioInitialise() before forking a child process which polls gpio pins for input. After forking the child, the parent process ...
0
votes
0answers
16 views

SPI to soft UART

Is there a way to use the SPI on pi for UART communications without any external hardware? Is there a library in C for this?
0
votes
0answers
59 views

RPI ERROR: Unable to open NFC device

I am currently following this guide: https://learn.adafruit.com/adafruit-nfc-rfid-on-raspberry-pi/testing-it-out After completing all the steps - inputting into the console: $ cd examples/ $ sudo ...
0
votes
0answers
338 views

Receive data from uart! Raspberry Pi mono c#

I'm new and I wanted your help please... From today, after updating libraries Mono C# on my Raspberry Pi Rev 2 Type B (wheezy), the communication via serial no longer works, it seems to me very ...
0
votes
0answers
278 views

Set default baud rate on /dev/ttyAMA0 and keep after reboot

I have a ITead Studio GPS attached to my RasPi Model B 2.0's UART serial port and it's specifications require baud rate to be set at 38400. I am using gpsd on Raspbian, which attempts to use baud ...
0
votes
1answer
62 views

Identifying USB devices [closed]

I have several RS232 to TTL UART converters plugged into my Pi. The problem is that their device assignments change sporadically. Sometimes the first device gets /dev/ttyUSB0, and another time ...
0
votes
1answer
127 views

Debugging problem with GPIO serial pins

I've been trying to run a port of a small RTOS called ChibiOS on my Raspberry Pi, and am having trouble with the serial communications. Specifically, when I use a UART connected at 3.3V to the GPIO ...
2
votes
1answer
148 views

Disable Raspberry Pi UART

Is it possible to disable UART in Raspberry Pi?? I undid what I have done to enable UART in Raspberry Pi, but UART pins(8 and 10) can't be freed because when I tested with an LED, it glows on ...
2
votes
1answer
196 views

Redirecting stdout and stderr to UART

I am building my own cross-linux-from-scratch (CLFS) system for Raspberry Pi. I already build whole system, I prepared SD card and now I try to boot. I am redirecting all kernel output to serial ...
1
vote
2answers
394 views

UART/Serial communication w/ mono

I have a diplay w/ touch functionality, that communicates via either I2C, SPI or Serial (datasheet). I want to use it in a mono-application. The display has sufficient power and is connected ...
1
vote
3answers
421 views

RF transceiver and XBee module, both need UART?

I'm working an a home automation project, using a Raspberry Pi. What I want to do is connect an RF 433 MHz transmitter to control RF-controlled light switches, and a ZigBee/XBee module to connect to ...
0
votes
0answers
223 views

Real Time Acquiring of ECG waveform and display on a web page for Raspberry Pi

Is it possible to display ECG waveform on a web page in real time for Raspberry Pi?? If so, please tell me how?? The ECG waveform will be acquired by MSP430 and will be sent via the serial port to ...
1
vote
1answer
85 views

remote command execution over UART

I have connected my computer to the raspi over UART and was wondering if I could remotely execute a command. My intention is to log stats of my raspi CPU usage on my computer at specific intervals. I ...
2
votes
1answer
414 views

Testing bluetooth communication on RaspberryPi

I am a beginner at RaspberryPi programing so I hope the question doesn’t sound dumb. I would like to test a communication between two bluetooh modules in SPP mode. Is it possible to connect them both ...
3
votes
2answers
644 views

Virtual UART ports

I want to use a Rpi to interface with 3 atmega ics in an embedded system but the pi seems to only have one uart port. I know arduino can emulate a serial connection over two io pins, will this be ...
1
vote
1answer
1k views

Enabling the UART port on a Raspberry PI

what does this statement imply: By default the serial port on the Raspberry PI is configured for console input/output. dwc_otg.lpm_enable=0 console=ttyAMA0,115200 kgdboc=ttyAMA0,115200 console=tty1 ...
0
votes
1answer
1k views

using serial interface /dev/ttyAMA0 crashes Raspberry Pi

I've disabled console on the GPIO serial interface, lowered the speed to 9600 and had some communications observed with minicom and a simple cat /dev/ttyAMA0 talking to an arduino all ok. Now for ...
1
vote
2answers
420 views

Disable DTR on ttyUSB0

I'm connecting from Pi to Arduino-clone board. The problem is, that I need to disable DTR line, in order to prevent Arduino from reseting on connect. I have read that on RPi is not possible to ...
2
votes
1answer
333 views

Same output on TXD and RXD

I wanted to read some data from an external microcontroller via the UART, but couldn't get any communication working. After checking the RXD and TXD pins, I saw that there is also a signal on the ...
1
vote
0answers
127 views

Can I use the TX pin as a normal GPIO output alongside serial communications on the UART?

I'm using the raspberry pi's UART to interface with a third-party radio. At startup, the radio reads its RX pin (the pi's TX pin) to determine which baud rate should be used. I'm using Gordon's ...
2
votes
1answer
1k views

Problem with UART

I've a Raspberry Pi Model B. I want to connect its serial output to my PC and view the logs generated by it. My serial to USB converter board uses FTDI FT232RL and supports both 3.3V and 5V (using a ...
1
vote
1answer
216 views

Is there a way to make a regular GPIO pin into a Tx UART pin?

I'm working on a project that is going to need two different UART interfaces. Is there a way to make a regular GPIO pin into a Tx UART pin, I don't need an Rx pin too. Is there a software solution ...
2
votes
3answers
322 views

UART sends but not receives but works if tx-rx are bridged

I havve this strange problem.. When I connect TX and RX pins together (GPIO 14 and GPIO 15, Rev1) and I run minicom, I see everything that I type.. so it works. But when I connect Tx Rx with an USB ...
1
vote
1answer
511 views

Why am I seeing some garbage bytes at the serial console login?

When I log into my serial console using screen /dev/ttyUSB0 115200, I see some garbage in the output: �� Arch Linux 3.6.11-10-ARCH+ (ttyAMA0) raspberry login: root �Password: Login incorrect ...
2
votes
1answer
643 views

Raspberry Pi on AVC-LAN / IEBus

I'm planning on using my Raspberry Pi in my car as an XBMC server. I'll be able to select songs/videos using the Android remote control app, but it occurred to me that it would be really neat if I ...
2
votes
1answer
837 views

USART resending Problem via console

I have some trouble with my USART interface. I short-circuited the RX and TX pins and tried to test sending stuff via the cli using these commands: sudo stty 200 -F /dev/ttyAMA0 cat /dev/ttyAMA0 ...
0
votes
1answer
248 views

Receive on usb bluetooth and send it to uart

Is there any easy way to receive data on cheap usb bluetooth dongle and all of data send to the UART in raspberry? Thanks for the answers!
0
votes
1answer
306 views

Do I even need a second board?

I am trying to use Raspberry Pi to stream and audio/video feed, and will probably be installing FFmpeg to do most of the work. I am trying to connect a camera and a microphone to the Pi board so that ...
3
votes
2answers
2k views

UART serial interrupt routine

Is there a simple way to use the registers as an interrupt trigger? I can make the application run in a new pid and poll for serial input using fork() I just need to read data, no write needed This ...
6
votes
6answers
5k views

How to get more than one uart interface

Ok, I have one uart interface (TXD GPIO 14, RXD GPIO 15). I want at least one more uart interface. Possible solutions: Bit banging: Use two unrelated spare GPIOs. I understand that timing is a ...
4
votes
2answers
1k views

UART Output working on 57600 Baud but with 115200 only gibberish

I've got a strange problem with serial output. Using Wheezy and 8 Databits, 1 Stopbit, NoFlowcontroll, NoParity (config as stated in eLinux Wiki). With 57600 Baud everything works fine but with 115200 ...
11
votes
3answers
655 views

How do I connect my printer to the serial GPIO pins?

I've purchased a Mini Thermal Printer from Adafruit. The documnetation states: This printer is ideal for interfacing with a microcontroller, you simply need a 3.3V to 5V TTL serial output from ...
6
votes
2answers
9k views

How do you set the UART speed?

How should you set the baud rate of the UART Bonus question: What baud rates are available on the RPi? Edit: Since reading up from Steve's answer, I have found that there are two UARTs available. ...