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.

0
votes
0answers
31 views

How to check if a COM port is being used

Im trying the check if a machine is connected to a device trough a COM port, i have tried comparing the dmsg output with the device plugged in and the output without the device plugged in, and they ...
1
vote
1answer
30 views

View Serial Port Parity Errors?

I have a device I'm trying to do some testing on. I know it connects at a baud rate of 115200, with 8 data bits, no parity and 1 stop bit. I'm attempting to prove these settings, or at least get ...
1
vote
0answers
35 views

Linux client program to connect to a virtual serial port

My connection: Linux with ser2net < RS-232 --- Ethernet > Linux I need freeware program to connect to a virtual serial port (RS-232) that i created with ser2net. Serial to Ethernet Connector ...
0
votes
0answers
31 views

Difference between PPP, QMI and AT commands

During the past 6 days, I had the chance to interact with an LTE modem (https://sixfab.com/product/quectel-ec25-mini-pcle-4glte-module/), I managed to set up 4G Internet access on a Raspberry Pi using ...
0
votes
1answer
18 views

How to setup connection from Win8 to ubuntu 18.04 via serial port RS232

I would like to connect from my Microsoft's Windows 8 PC, to a PLC(Advantech uno-2372g), via USB-to-RS232 to a serial port on the PLC (ttyS0), using putty. I am trying to connect to the PLC, but it ...
1
vote
0answers
22 views

Connect Serial Port through COM port or USB adapter (different models)

I use a program where I need to specify a COM port. Can I connect via COM port (/dev/ttyS0) or through different models of USB-RS232 adapters (on /dev/ttyUSB0), configured so they always bind to the ...
0
votes
0answers
11 views

running a terminal over PCMCIA serial port in unix

I'm currently doing a microcontroller project that requires a serial port, but for testing purposes, I require two serial ports and terminals working with both of them. My computer has one native ...
0
votes
2answers
25 views

Access serial port of sshfs mounted filesystem

I'm trying to read /dev/ttyUSB0 of another computer mounted via sshfs, however commands such as cat /mnt/tmp1/dev/ttyUSB0 return "Permission denied" (I'm mounting the filesystem to /mnt/tmp1). I've ...
0
votes
0answers
50 views

Serial ports sometimes having problems

I am using Centos 7, with kernel version 3.10.0-862.2.3.el7.x86_64. I was able to use all the 4 serial ports normally (RS485) and I do not usually touch the computer since it is just collecting data. ...
-2
votes
1answer
65 views

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

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
96 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
20 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
40 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/...
0
votes
1answer
29 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
84 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
54 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 ...
3
votes
2answers
238 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
93 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
97 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
27 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
279 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
27 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
147 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
15 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
201 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
24 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
390 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
523 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
56 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
404 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
76 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
94 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
80 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
347 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
290 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
466 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
143 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
372 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
261 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
175 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
121 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
445 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
674 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
262 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
159 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
60 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
246 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
164 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
279 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
22 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 ...