I'm using sim900 modem with raspberry pi, I'm able to connect to server using AT command for TCP, but when I try to send mqtt Publish packet as follow(I used tcpflow to get this packet from mosquitto library):
Serial.print("0");
Serial.print("0x10");
Serial.print("0x0");
Serial.print("0x8");
Serial.print("ABC/XYZ");
Serial.print("HELLO");
Serial.print("0x0");
it doesn't work.
Follow this tutorial to connect internet on Raspberry Pi using SIM900 modem.
Download 'sakis3g.gz' from Here.
Use Mosquitto client library for MQTT pub/sub functionality.
It worked for me :)
Steps to enable internet on 'Raspberry pi' using SIM900 :
Enter this on terminal sudo apt-get install ppp isc-dhcp-server usb-modeswitch
Then download sakis3g from Here
Unzip package using gunzip sakis3g.gz
Make file executable chmod +x sakis3g
Run sakis with GUI option sudo ./sakis3g --interactive
Now follow onscreen instructions. Good luck! :)
Related
I need to use ttyS0 as serial communication in python script on my coral mini board, I disabled system service:
sudo systemctl stop systemd-logind
sudo systemctl stop serial-getty#ttyS0.service
But seems there still have output from Serial console in ttyS0 like:
IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
spidev spi0.0: SPI transfer timed out
I would like to know how to make the ttyS0 clean as no any other process using it, if its possible, better to do it in runtime.
Thanks!
I successfully implemented this, which blocks all internet connections on my Linux machine UNLESS it connects via a specific VPN :
https://www.comparitech.com/blog/vpn-privacy/how-to-make-a-vpn-kill-switch-in-linux-with-ufw/
If I manually execute openvpn3 session-start --config ~/Desktop/config.ovpn, it successfully connects via the VPN.
I used to have this command in a script (that has #!/bin/bash as header) which ran at device bootup without any issues, UNTIL I configured ufw for the killswitch above (now ufw runs on device bootup).
I use openvpn3 so using instructions in the above tutorial for openvpn commands didn't work at all.
I even tried using a sleep in my bash script to get it to wait a while until after bootup. Doesn't work. But if I issue the connection command manually in the command prompt, it works.
Please help! I need it to connect automatically. Much appreciated!
After spending a whole day on this, I figured out a solution. I found an article that guided me : https://www.howtogeek.com/687970/how-to-run-a-linux-program-at-startup-with-systemd/
I set up a service item using systemd (systemctl) just for that command to connect. Here is what my entry looks like :
#/etc/systemd/system/connectvpn.service
[Unit]
Description=Connect VPN
After=ufw.service network.target
Requires=ufw.service
[Service]
Type=oneshot
ExecStart=/usr/local/bin/connect
#/usr/local/bin/connect
#!/bin/bash
openvpn3 session-start --config /home/xyz/Desktop/config.ovpn
Working nicely now, connects to the VPN on bootup.
I'm trying to remote debug using gdbserver.
I connect my target device to my PC through USB port using this command to open terminal controlling my device :
minicom -D "/dev/ttyUSB0".
Now on my target device, I need to run gdbserver with this cmd:
gdbserver /dev/my_USB_serial_port my_Program.
However, I can't find ttyUSB0, all I got ís a bunch of ttyx(with x is a number) as below:
~ # /dev/tty
tty tty14 tty20 tty27 tty33 tty4 tty46 tty52 tty59 tty8
tty0 tty15 tty21 tty28 tty34 tty40 tty47 tty53 tty6 tty9
tty1 tty16 tty22 tty29 tty35 tty41 tty48 tty54 tty60 ttyS0
tty10 tty17 tty23 tty3 tty36 tty42 tty49 tty55 tty61 ttyS1
tty11 tty18 tty24 tty30 tty37 tty43 tty5 tty56 tty62
tty12 tty19 tty25 tty31 tty38 tty44 tty50 tty57 tty63
tty13 tty2 tty26 tty32 tty39 tty45 tty51 tty58 tty7
How could I find which one is the correct serial port of my USB port ?
Update 1: As Employed Russian mentioned in the answer, I got confused about the USB port but I still couldn't connect to gdbserver using his command.
However, I can't find ttyUSB0
You are confused -- of course you will not find ttyUSB0 on the target -- the target doesn't have anything plugged into its USB port.
On the target, you want to run gdbserver - my_Program &, then disconnect minicom, and finally use gdb and target remote /dev/ttyUSB0 on the host.
Make sure getty isn't running on the same serial port as gdbserver on the target.
If you've got an interactive shell with minicom, check the serial port (usually ttyS0) on the target that's connected to it. If it's ttyS0, you start gdbserver on some other port, and connect another FTDI cable from that port to a second USB port on your host.
I created Kaa sandbox instance on the AWS Linux host. I am getting some of the issues
Still I am not able to see the management button on the kaa Sandbox console.
I am not able to connect AWS with using ssh. I followed all the required step to connect to AWS Linux host, but not lucky to connect.
My problem is that, I would like to change the host IP in the sandbox setting with my AWS linux host IP, so that my end point device gets connected to host,
Still I am struggling with above points. Please advise.
Regards,
Prasad
That seems to be an issue with the Kaa 0.10.0 Sandbox for AWS. We created a bug for tracking this.
For now, you can use the next workaround:
echo "sudo sed -Ei 's/(gui_change_host_enabled=).*$/\1true/'" \
"/usr/lib/kaa-sandbox/conf/sandbox-server.properties;" \
"sudo service kaa-sandbox restart" | \
ssh -i <your-private-aws-instance-key.pem> ubuntu#<your-aws-instance-host>
Note: this is a multi-line single command that works correctly in bash (should also work in sh and others, but that is not tested).
Note 2: don't forget to replace
<your-private-aws-instance-key.pem>
<your-aws-instance-host>
with the respective key name and host name/IP address.
I'm trying to set up a pair of serial ports between my QEMU host (Debian Jessie x86_64) and guest (also Debian Jessie, but on ARM). Everything except the serial port part works.
I'm really new to QEMU so there might be a better way but I've tested the following flags when running QEMU:
-chardev tty,id=mytty,path=/dev/pts/2 (/dev/pts/2 & 3 are up with socat)
-chardev pty,id=mypty QEMU opens a PTY but when I try to read or write from host get permission denied.
In either case I can't find the ports in my guest. /dev/pts is empty and in /dev there are only tty and ttyAMA3. So, my problem is setting up communication in general and I'm especially curious on where the ports are on my guest.
I found a solution to my own question. First the device tree was incomplete so I needed to add 3 additional uart ports. That's the reason I could not find my ports in the guest.
Second, I needed to tell QEMU to use on of the ports as stdio: -append ... console=ttyAMA3 and -serial mon:stdio. Then I'm able to, with -serial pty, link QEMUs ttyAMA* to pts/* on the host.