Hi, it sounds like you’ve made some progress, but getting to the finish line can be pretty frustrating…
First, you haven’t specified which modem device you are using. Are you using the Nova M (with U-Blox SARA R410M-02B) or something else?
Second, you indicated that you began using WIndows, but are now struggling with a Raspberry Pi. Are you running a Linux variant on the RPi? I’ll assume for the remainder that you are running Linux.
By coincidence, I recently posted the steps I have followed to establish a ppp connection:
https://community.hologram.io/t/connecting-novam-to-cellular-network/2632/22
Several folks have contributed to the thread and now it includes both,
- how to set up a ppp connection
- discussion about performing data transfers using AT commands (w/o ppp)
including pros and cons of each.
Which way is “best” depends on your goals. I’ll just say that if you set up a ppp connection then at that point your system is connected to the Internet in such a way that individual programs can use the connection transparently. That is, your computer will behave as it does when it has a wifi or Ethernet connection; no individual program will have to do anything beyond create a socket connection or invoke the full array of Linux tools or whatever. The operating system will use the ppp connection to route packets in and out as you would expect.
My understanding is that when you use the Hologram CLI command,
Hologram network connect
under the covers the CLI establishes a ppp connection. And, no, the CLI does not close the ppp connection (unless you run “Hologram network disconnect”). Of course, the connection can close even without any request to close it.
Now, you say you are not a professional coder–nothing wrong with that–but you haven’t indicated your experience level or skill set so it doesn’t make sense to offer specific guidance.
I will make this suggestion: if your goal is to produce a daily 50k image on yourr RPi and move it a remote computer, you must decide:
- shall the image file be sent from the RPi to the remote computer (“push” the image from RPi to remote)
- shall the remote computer fetch the image from the RPi (“pull” the image by remote from RPi)
If the remote computer is at a known URL (or a fixed ip address) then pushing from the RPi will, generally, be easier. The reason for this is that mobile devices (e.g. RPi with a cellular connection) do not get fixed ip addresses and are generally hidden behind some sort of firewall in such a way that their ip addresses are not easily discovered. if the remote computer is not mobile, it will always be available at a certain URL, so the RPi can easily locate the remote, while the remote cannot locate the mobile RPi.
You will not, without performing magic tricks, be able to connect to your mobile RPi using Putty or other such tools.
If you run ifconfig and you do not see the ppp0 interface then you do not have a ppp connection. Either it was not set up in the first place or it has disappeared. I urge you to take a look at my other posting.
As far as a tutorial, there’s really nothing very special about sending a file. If you want to use AT commands then you must find details in the AT command set documentation (find a link in my other posting). Using the AT commands you can set up a socket connection or perform a file transfer using FTP. If you set up a ppp connection you can transfer files in all the ways available on any Linux system.