Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [serial-port]

A hardware interface commonly found on older PCs, usually with a 9-pin DE-9 socket/plug, on networking devices or servers also with RJ-45 socket/plug (otherwise commonly used for ethernet), or with a (much wider) 25-pin DB-25 socket/plug. Two common standards used with such an interface are RS-232 or RS-422.

-1
votes
1answer
35 views

can not read anything from serial port until i test something with “Screen” command

I think something wrong is in my setting (serial port, termios flag). when I run my code, it is waiting to receive data, but nothing happens, than I close my program and run screen command, it ...
1
vote
0answers
30 views

Serial Port ttyS0 and ttyS1 not showing in dmesg

My terminal has 4 Serial ports. I try to find them with command dmesg | grep tty. This is what I get: [ 1.317597] serial8250: ttyS2 at I/O 0x3e8 (irq = 4) is a 16550A [ 1.317730] serial8250: ttyS3 ...
0
votes
0answers
18 views

How do I force Ubuntu to use a device as an USB serial device?

So I have a device here that doesn't get recognized as an USB serial device. (so no COM-port is dedicated to the device) Can I force Linux to use my device as an USB serial one and give it a COM port?...
0
votes
0answers
29 views

How to create a new character device under /proc/device file?

I am trying to create a node with mknod /tmp/ttyACM0 c 166 0 command but then No such device or address error returns when I try to open serial port with ttyACM0 because there is no device in proc/...
-1
votes
0answers
6 views

How to connect guest COM port from Host in VirtualBox in Mac for MODBUS communication [migrated]

I am using pymodbus library to connect to a MODBUS master in the Windows OS (which is a guest OS in Virtual Box) and the host OS is Mac. I followed steps mentioned in this SOF answer. So, I created ...
0
votes
1answer
28 views

How to Change the Serial (RS232)Port Number

I have the Adventech terminal which have 4 Serial port, and our application are using only 1 (ttyS0) port for communicate the POS printer. But few days the printer has not able to communicated the (...
3
votes
1answer
77 views

Connected using screen over RS-232. How do I transfer a file to my local system?

I'm connected to a device over a serial cable and using screen I have full access to the remote system. How do I transfer an entire file(s) to my local system? Not just the contents of the file, I ...
0
votes
0answers
16 views

send hex as characters to output to remote end

I'm doing a project for a microcontroller that involves sending and receiving special (non-printable character) data through its serial port. I found myself a simulator (ucsim) so I can test things ...
2
votes
2answers
99 views

Use remote serial port as a local one

I am trying to develop some software for my charge controller but the only device that I can use it with is my raspberry pi (just because I don't want my PC downstairs) anyways it communicates via /...
0
votes
1answer
69 views

The linux system keeps changing the baud rate of the port to default (9600). Is there a better way to change the baud rate of the port permanently?

I changed the baud rate of my linux USB port from 9600 to 115200 using the command # stty -F/dev/ttyUSB0 115200 because the FPGA that I am working on is programmed for a baud rate of 115200. I cross-...
0
votes
0answers
59 views

tcpdump usbmon module output explained

Running the command: tcpdump -qAXni usbmon3 -s 0 I am getting this output: 02:32:04.781964 BULK SUBMIT to 3:16:4 What does the last number after the colon (4) represent? How can I identify it in ...
0
votes
0answers
21 views

gpsd works only once

I am working on connecting a Garmin Oregon 750 GPS to a Linux box using gpsd. The final goal is to use it for navigation inside Qgis. So far I've managed to make it talk to the computer using gpsd, ...
2
votes
2answers
116 views

Serial port program to write file/read to file from tty?

i'm looking for some commandline program which I can use to send and receive data to/from serial port. I would like to automate my testing process - start test script which will send file to ttyPC, ...
0
votes
0answers
21 views

Chained serial connections to Linux machines with picocom and screen issues

I am connecting via serial terminal (picocom) to a Linux machine which at the same time has several serial interfaces I want to use. In that Linux machine I can only use screen to do so. My problem is ...
1
vote
0answers
74 views

Listen in to data read from file descriptor to ttyS

I have a serial device under /dev/ttyS0 and an application that is reading from the serial device (but not writing to it). I wanted to listen in to the data that is coming in on the serial device but ...
1
vote
0answers
13 views

Assigning users to serial device server

I'm working on a server (CentOS 7) that will be connected to a serial device service. I also have 6 client machines. The SDS makes the devices show as actual devices in linux and can be controlled by ...
0
votes
1answer
115 views

create pty and connect it to a serial port /dev/ttyUSB0

Problem: I have two Linux machines connected with a serial interface. I use ppp to communicate between them (I have to since it is a project requirement). Communication speed is at 9600 bits/s. I ...
0
votes
0answers
21 views

SER2NET “Tee or Wedge”

I am successfully using SER2NET on a Raspberry Pi to translate RS-232 data to Ethernet. But I would like to "watch" the data coming from the serial port for a certain string, and if there is a match, ...
1
vote
1answer
285 views

Virtual serial port between docker containers

I can create two linked virtual serial ports on a Linux system with socat, and pretend one end is a serial device, and the other one is some code that uses the device. The socat command would look ...
2
votes
0answers
344 views

How to have local echo on with `screen` command?

I tried screen /dev/ttyUSB1 9600,echo but I still don't see what I type.
0
votes
0answers
48 views

Turning USB into a terminal

I have a hardware device that connects via USB without creating a specific /dev/something. It does change the time on /dev/ptmx and /dev/char but that's about it. All I know are the VID:PID of the ...
0
votes
1answer
267 views

Dpkg-reconfigure openssh-server fails on boot

When I boot the linux, dpkg-reconfigure openssh-server fails and the booting gets stopped there. But when i press ctrl+c it resumes the booting with dpkg-reconfigure failed.
0
votes
1answer
42 views

How to use Libudev to find out which ports are connected to my Usb

I made a kind of module. Different sensors are placed in the module. I connected the module to Raspberry Pi through RS232 converter. I am using Libudev to automatically find out which Pi port has ...
1
vote
0answers
74 views

Is there any standard for naming RS-485 tty devices/device aliases in Linux?

I know, that there are some standards in tty naming. There is ttyUSBx for USB to serial converters, ttySx for RS-232, ttyAMAx on ARM devices, but I can't find anything about conventions in RS-485 ...
0
votes
1answer
53 views

UART to UART tcp/ip connection

Need to transmit and receive data(TCP/IP) between 2 raspberry through serial tx/rx pins (/ttyAMA0). Best way to do it? Better if this will be done from kernel space. Thanks!
1
vote
1answer
209 views

How do I use jpnevulator to capture and log the serial traffic between an application and hardware serial port?

OK, I've been googling for hours so I obviously have not been able to understand the answers to the various questions that have already been asked about this subject. I am hoping that, by asking the ...
1
vote
0answers
222 views

Debian not recognizing my ttyS0 / console redirection not working

I have a fitlet2 (https://fit-iot.com/web/products/fitlet2/) which has a serial port. I can connect to the serial port of the fitlet2 with screen from my computer (screen /dev/ttyUSB0 115200) and ...
0
votes
1answer
346 views

Android Serial Port is being used for no permission to open

I have a Wandboard IMX 6 with Android OS. I can't read RS232 data. I was wrote an app for this on QtCreator with C++. I have an issue. When i pressed the connect button i take serial port is being ...
0
votes
1answer
110 views

Getting rid of a serial console on Respeaker Core V2

I have a Respeaker Core v2.0 and I would like to use the UART interface (this board has a USB to TTL adapter connected to the Uart port) in order to make this board communicate with another one. ...
2
votes
1answer
252 views

ppp between two machines over serial without a modem

Moving question from stackoverflow.com Unfortunately can't delete this question from stackoverflow.com. I'm trying to setup a PPP connection between two Linux machines over a serial line. I followed ...
0
votes
1answer
207 views

How to send F10 with gtkterm?

How can I send F1..F12 especially F10 in gtkterm? I have to press F10 at the right moment to select the boot menu of an APU2 system.
0
votes
2answers
136 views

Do “serial ports” or “parallel ports” apply to character devices only, but not to block devices?

From http://haifux.org/lectures/86-sil/kernel-modules-drivers/node10.html A Character ('c') Device is one with which the Driver communicates by sending and receiving single characters (bytes, ...
0
votes
0answers
110 views

libvirt and kvm/qemu, password on console redirection/serial doesn't work

I have added a serial,and a console to connect my vm without X using this command. virsh console myvm Unfortunately my vm has a luks encrypted root and..I can put the password only from graphical ...
2
votes
0answers
388 views

resetting serial port configuration

stty allows to read a serial port configuration. I have noticed that when some program opens, configures and later closes a serial port the last serial port configuration is still present in the ...
0
votes
1answer
494 views

sniffing serial port - jpnevulator sniffs only some bytes

I use jpnevulator to sniff an application which reads a serial port: jpnevulator --tty /dev/ttyS0 --read Let's assume that the following bytes are sent to the serial port: A B C D E. Sometimes ...
-1
votes
1answer
209 views

Send program's serial output to pseudo-terminal used by serial sniffer such as jpnevulator [duplicate]

I am running an application that communicates through a real serial port e.g. /dev/ttyS0 to a remote device. I can configure this application to use /dev/ttyS0, /dev/ttyS1, etc., by passing the ...
2
votes
1answer
106 views

Troubleshooting an RS-485 communication

I have an ND-6021 Analog Input Module. It is an RS-485 device that can set a variable output voltage based on the command it receives. I am trying to make it works under a Linux Debian Stretch. I have ...
0
votes
0answers
30 views

Why serial of libvirt using pts/* is avaliable only to root?

I have a old vm,no networking(sic!) so I use the old good serial for comunicate from host. On libvirt/qemu is possible to setup a pseudotty pts like a real serial port. Serial is ok on guest,on host ...
0
votes
1answer
162 views

Knowing when a write() on a serial port has finished transmitting data

I need to synchronize an IO pin value with a write to a serial port from user space (because I wasn't yet able to do it from kernel space - see my other question). My code (leaving out error checking) ...
2
votes
1answer
115 views

Hardware controlled RTS on tty

I have a UART whose RTS pin is connected to an external RS485 transceiver, so that asserting the RTS pin would set the transceiver to send mode. I thought I could configure the serial port to use the ...
1
vote
0answers
248 views

How to get a serial terminal emulator in linux to ignore RTS & DTR?

I purchased a generic 8-pin ESP8266 off Amazon. It came loaded with some "AT" command firmware that acted like a modem. I connected the module to an FTDI1232 which is a USB connected UART that acts ...
2
votes
1answer
20 views

Thermal printer only print after send a second output data to tty port

I have a PCI Serial Card installed on a POS computer and I'm trying to install an old thermal printer in it. The test command ls > /dev/ttyS4 works well, but only after the second time I send it. For ...
2
votes
0answers
327 views

/dev/tty* serial devices are in group “root” for a second before they are switchted to group “dialout”. How to make them start out in “dialout”?

When I plug in a usb-to-serial device, it takes some time for the device to be switched to the "dialout" group (it starts out in the "root") group. This wreaks havoc with some client software that ...
0
votes
1answer
40 views

Has the /sys/bus/usb/ the same structure in all Linux distributions

I am porting mono app from Windows to Linux. The app communicates with external board. This board is visible as three virtual serial ports. Every plays a different role. The app is automatically ...
1
vote
0answers
64 views

How to recompile and run a prebuilt linux kernel driver as a custom module?

I am able to create a custom basic module (hello wrold kernel) and use insmod to load it into kernel space. However what I need now is to be able to use slip.c code by its entirety (copy and paste) ...
3
votes
1answer
153 views

Serial port ignoring custom divisor

I am trying to run a serial port at 3.25Mb/s by applying a divisor of 2 to a baud base of 6.5Mb/s. I am using an IoT device (Telit HE922-3GR) running android 6 with built in serial ports, the proc/tty/...
-2
votes
1answer
16 views

LoRaWAN wireless dongle not responding to AT command [closed]

0 down vote favorite I want to configure a wireless LoRaWAN dongle via AT commands by using the echo command in the ubuntu terminal but the dongle doesn't seems to be responding with any feedback ...
1
vote
0answers
202 views

Why does my serial port give a response without a loopback cable?

I'm new to using serial ports, and I have a loopback cable for serial on a Centos 7 machine. I have something in python that tests the port, but I've found that the program returns the expected ...
1
vote
2answers
616 views

Retrieve file over serial without kermit and lrzsz

I have an embedded Linux on a custom board and I would like to send and receive file over its serial port. The only way to communicate with this device is over serial and the device offers a console ...
1
vote
2answers
98 views

How to give a tty a mode other than 640 and have it persist through reboot

I have an embedded device (Nvidia Jetson TX2 running Ubuntu 16.04) in a carrier board and need to use the serial port. The serial port on the carrier board maps to ttyS0 which by default is owned by ...