I'm trying to create serial communication in NetBSD. This
communication will connect the computer with a controller via RS-485.
The problem is that I don't know if it necessary some configuration or driver to do it.
Specifically, the communication will be through the RS-485 port. I've tried to use /dev/tty01, but there are no pulses in serial output.
Are there some configurations , drivers or codes necessary to open, send and receive serial data in NetBSD?
I didn't have sucess until now.
Thanks
Nothing special needed.
If your serial is a real serial, then you could connect via:
# cu -l /dev/tty00
if your serial is a serial over USB then:
# cu -l /dev/ttyU0
However in both cases you have to be root, or change permissions on the device.
If the output is not visible, then adjust the speed with -s switch.
Related
I am using socat to create a virtual serial port connection to a TCP client in Linux
eg sudo socat pty,link=/dev/ttyVirt0,raw,echo=0 tcp:192.168.1.251:5001&
This all works fine but one of the 3rd party applications I use with this virtual serial port uses hardware flow control. While flow control is not needed for the virtual serial port, I need to be able to assert RTS (logic 0) from the virual port ttyVirt0 to enable this application using it to send data.
There must be a command line option to support this? Does anyone know?
I am not able to use ttyAMA0 serial port on the RaspberryPi3 from a cpp app when I build the image by using Yocto. If I use the original Raspbian image, on the same hw, then it works perfectly.
I followed the indication on meta-raspberrypi docs
docs
by adding
ENABLE_UART = '1'
and SERIAL_CONSOLE = '115200 tty1' ( to redirect to another tty the console )
and MACHINE_FEATURES += " pi3-disable-bt"
but nevertheless the RaspberryPi is not moving the UART_TX0 pin when I try sending some data to the uart. this instead works correctly with the original Raspbian image.
What should I add or modify ? it is not clear nor there is other documentation about this.
Usually the Raspberry Pi 3 has two serial ports, one via UART and the other on the GPIO pins. The first one has it's name commonly known as "ttyAMA0" the second one uses the name.
Try one of them if doesn't work you will have to look the name that it's being recognised and use it as your device name.
ls /dev/serial/by-id/
My device is a ARPI600 and when I connect it I setup my serial communication like this
serial.Serial("/dev/serial/by-id/usb-Silicon_Labs_CP2102_USB_to_UART_Bridge_Controller_0001-if00-port0", baudrate=115200, timeout=1.0)
First allow me to say that I don't have any experience developing drivers for OSX, nor drivers for Windows. So, there are a lot of things that I don't understand about how drivers work; I'm sure it'll be evident in my question.
I have a modem that is able to open and close TCP/UDP sockets using AT commands. I would like to create some kind of program (kernel extension? driver?) that implements a network driver, converting the network interface calls into AT command serial messages.
That's the basic jist of it. I'm essentially asking if anybody can point me in the right direction / give me a high level overview of how they would approach it and what Apple guides to focus on.
The XNU networking stack -- like most network stacks -- expects network devices to send and receive IP packets directly. It isn't tooled to work with network devices that handle part of the network stack (like TCP or UDP) internally -- it won't be possible to implement a network driver which uses this device.
You might have more luck exposing this device as a SOCKS proxy. You will need to write a userspace daemon which listens on a TCP port on localhost (on the computer) and relays traffic to the serial device; once that's done, you can set the computer to use that device as a SOCKS proxy in the Networking control panel.
(As an aside: most devices that implement this type of interface have a very low limit on the number of open sockets -- often fewer than 10. They're unlikely to be able to handle the network load generated by a desktop OS.)
I have to make a windows based application for which captures network traffic per application where some of running application uses same port number for sending and receiving the packets.
I have used winpcap and successfully captured and filtered them port wise and destination wise but I dont know how to capture them application wise that means how to know application information from ip packets.
Is only winpcap can solve the problem or some other api's or library shoud be used.
Can we get the application information from which packet is generated from packet header?
**
Can anyone give me example that uses iphlpapi and winpcap in vc++ for capturing network traffic per application.
**
I don't think this is possible with winpcap.
Take a look at Windows Filtering Platform. It's not advanced at all.If you look in the samples you can find one which does exactly what you want.
winpcap doesn't have a good way to tell what process is sending what data.
But windows does.
try using
netstat -a -o
netstat is a program that tells you what ports are being used on your terminal.
-a switch says, "show me all the ports"
-o switch says, "show me the pid of the processes using this port"
you can't see what port your processes are sending on, but you can see what ports are receving on for udp packets.
for tcp packets you'll see all the info you could want, includeing the remote connections ip address.
I am running a USB cell modem via PPP in Embedded Linux. I can use AT commands via minicom to connect to the modem and interrogate the signal strength (AT+CSQ) when the PPP connection is not active. However, when it's active, this is not possible.
Is there any way to retrieve the signal strength from a PPP connected USB cell modem while the PPP connection is being used? I am open to an API or any other method available.
I don't have a umw190, but the Linux driver for the modem should have more than one ttyACM character device available. Use one for PPP and the other for AT+CSQ. Check dmesg for cdc_acm to see.
If your embedded device has udev then both devices should automagically appear in /dev. If not you'll have to mknod more. Off the top of my head major number is 166 for cdc_acm.
What does the physical setup look like?
1. Are you using a modem that is on a board designed/printed by the same company as your SBC?
2. Is it connected via something like PC104 serial or USB?
3. What specific modem are you using?