On an embedded Linux system running Busybox I am trying to receive bytes over a serial port and echo back everything received. The system setup is like this: Linux <-USB-> FTDI chip <-UART-> MCU On the UART line I have a logic analyser monitoring the data between the FTCI chip and the MCU. Both th…
Tag: serial-port
Bluetooth Serial Port on Raspberry Pi & something weird happened when using IDE and terminator to run python files
I am doing a project using the Bluetooth serial port. It is about the message communication between cellphones and the Rpi. I typed ‘sudo rfcomm watch hci0’ on the Terminator. The code on Python is simple: only assign the port address (‘/dev/rfcomm0’) and readline(). At first, things w…
How to initialize pppd connection witsh RS232 modem?
I trying to run the pppd daemon on my embedded board. When I connect the modem to USB and run “pon provider” the initialization is correct (I get the IP address and in “ifconfig” I have ppp0 interface) “provider” file: “mobile-modem.chat” file: However, I would …
Why cannot I read data from a serial port?
I have faced the following problem: I wish to read data comming to my serial port on linux. Data are send from an external device with standard serial settings. I’m sure that the external device sends them, that has been already checked. However, on linux all i can read is an empty byte. What am I setti…
Tcl refuses to set 76800 baud rate for serial channel on Linux
I have an FTDI USB/serial device at /dev/ttyUSB0. I set up my channel with which works just fine for Tcl on Windows. On Linux, baud rate queries show and I get all the garbage you’d expect from trying to communicate at the wrong baud rate. I saw this previous post: fconfigure refuses to set baud rate to…
/dev/ttyACM0: permission denied on openSUSE
I am trying to use an “Arduboy,” based on the Arduino Leonardo, with the Arduino IDE. I cannot upload the example code, however, because of the following error: Before you mark this as a duplicate, here are all of the things I have tried Adding myself to the dialout group that /dev/ttyACM0 can be …
Serial Input in Ubuntu, Usb to serial converter (Pl2303 – Prolific) not working in ubuntu 18.04
I am trying to read input from a Electronic weighing scale (Weigh sensor) connected to Ubuntu enabled UDOO board using a Prolific PL2303 serial converter cable (CA-US9), but am unable to read any input from the sensor. To monitor the input I have tried using (Coolterm & GTKTerm), assuming an issue with th…
Serial port hangs on close()
I developed this simple kernel module, which emulates a serial port by using a FIFO queue and a timer (read from hardware : out from the queue, write to hardware : insert in the queue). Source code is shown next. Then, I wrote a simple test-application which configures the port settings (baud rate, parity, st…
How do you check if a serial port is open in Linux?
How does one check if a serial port is already open in Linux using Posix/C functions? I want to check the status of the serial port to check if the serial port is open or not. I would like to know what methods work for: Checking the file descriptor to see if the serial port is open and Checking the
usleep vs std::this_thread::sleep_for, when write/read on a linux serial port
I have created a c++ app that needs to connect to a modem via a serial port in order to give AT commands. I’ve followed the following answer: how to open, read, and write from serial port in C and it works great. In some point of the code it is mentioned that the working thread should sleep for enough