Hello,
we use several RG530F based EVB-Kits (5GDM01EK) in one of our projects.
We noticed that after disconncting USB from the host computer the modem
autonomously reply on ongoing ping requests.
Surprisingly this still works after disconnecting the board from its power supply
for a couple of seconds and reconnecting to power again (but still the host
computer USB-connection not established again)
This makes some testing aspects difficult, as a quick check if the connections
to the modems is done via pings.
Can this behavior switched off somehow?
Hi @Richie
Could you provide the accurate OC number and picture of the EVB kit. Is this purchased from Quectel？
Thanks
Hi Puck-Q,
sorry, i likely used an internal product code from our seller
and i don’t know where i can find an “OC” number.
It is a Quectel product, the user guide file is named:
Quectel_5GDM0x-EV_EVB_User_Guide_V1.0.0_Preliminary_20230202.pdf
The first page shows the same naming: “5GDM0x-EV EVB”
We received it fully assembled in a chassis, according to a colleague the
inside board looks like the pictures in chapter 2.1 Top and Bottom views.
Hi @Richie
Thank you for the information.
As you mentioned “autonomously reply on ongoing ping requests.”, could you provide some screenshots or logs to help me understand what this means? Or are you using the USB work as a usb network card, but you disconnected the USB?
Thanks
Hi Puck-Q,
Your assumption is correct.
the EVB is connected via USB3.1 to the host computer and of course
to a 12V power supply. In our case Laptops with Ubuntu 22.04 are used
as hosts, but our project partners are using Mini-PCs / Raspberrys.
Ping is not started from the host computer side, as we have no access
to the host computers of our project partners.
Our core is setup to provide static IP addresses to the modems.
To check whether the modems are connected we execute ping from a
(mobile edge) server, directly connected to the 5g network, to the modem.
We start the ping with everything connected and working fine.
If we disconnect the USB-connection between modem and host, the server still
receives ping replys, so they must be coming from either the modem or something
else running on the EVB. If we additionally switch off the power supply, of course
we do not longer get ping replys.
After reconncting the power supply we receive ping replys again. With the host (USB)
still disconnected. So the connection cannot been re-established by the host (in our
case ModemManager) but by the board itself.
Hope this description helps, i think a log/screenshot would not provide much insights.
My question is: can this behaviour controlled / switched off?
We would prefer to have the ping reply only be created by the OS running
on the host computer, so e.g. can be verified with wireshark
Thanks