OpenWRT WPJ428 - EM7565

Context

After reading a lot about the EM7565 configuration under OpenWRT (the board I use is https://innovelec.co.uk/products/wpj428/), I’d rather ask here for advices before beginning the integration/software development (because several posts mentionned issues and quite complex troubles around it).

Need

I need to make a hotspot bringing Internet from the EM7565 to the on-board Wi-Fi modem. I develop under Linux (Ubuntu 18.04 or higher) and I use OpenWRT for the OS of the board.

Question(s)

I am a bit loss on “the correct way” to achieve this. May someone give me advices about the steps I need to do in order to obtain this hotspot behavior?

@hadrien.toma

So all the EM7565 will do is give the system an internet connection via either a PPP or RMNet connection (see attached). Obviously the WiFi management has to be done on the SBC and also the bridging between the two interfaces (wifi to the one created by the EM7565). Its all down to the application programming on the SBC’s OS, not the functionality that the EM delivers which is one small part.

1aec569af75a1ab07c66bf85086071fc482f614b.docx (347.1 KB)

Regards

Matt

1 Like

Thank you Matt, this is clear and useful.

I think I see how to make a Wi-FI access point on the SBC and I built bridges in the past but never with PPP or RMNet, may I ask if you have some documentation/links where I will be able to learn to manage it?

Also, the documentation you shared me seems to be for the MC73xx, do you mean it is also applicable for my EM7565?

@hadrien.toma

Yes its an old document written before the EM7565 existed but the underlying protocols are still valid and it still works. Re PPP there is a lot around the internet as it is the traditional way to dial out with a modem, it has a number of disadvantages.

RMNet is Qualcomm proprietary so there isn’t any documentation around.

Regards

Matt

1 Like

Alright, thank you :pray: :slightly_smiling_face:

I read the document sent by @mlw (thank you again, it really helped me to more understand how a modem works with an OS). Unfortunately it seems I have an issue on the hardware detection of the modem. Maybe I need to install a driver or something like that to help OpenWRT to take the device into account but I don’t know how to go with this :persevere:

** Maybe someone can point me to the correct procedure to be able to have the modem ready (as a reminder, at the end, what I will need is a bridge between the EM7565 and the on board Wi-Fi modem so I need a modem “ready” for the bridge adventure which will arrive next)? **

To precise the context, here are the commands I ran and their results:

  • Logs from serial port: enclosed file log-file-minicom.txt (59.7 KB) .
  • uname -mrspvio :arrow_right: Linux 4.4.60 #35 SMP PREEMPT Thu Jul 18 11:32:56 +08 2019 armv7l unknown unknown GNU/Linux
  • ip: enclosed file ip-output.txt (3.3 KB)
  • ls -l /dev: enclosed file ls-dev-output.txt (5.0 KB) (I especially noticed ppp, cdc-wdm0 and ttyMSM0).
  • cat /sys/class/net/wwan0/qmi/raw_ip :arrow_right: N
  • uqmi -s -d /dev/cdc-wdm0 --wda-get-data-format :arrow_right: ^C"Failed to connect to service" (^C means that I needed to kill the process because it was not responding, even after a long time).
  • uqmi -s -d /dev/cdc-wdm0 --get-pin-status :arrow_right: "Not supported"
  • uqmi -d /dev/cdc-wdm0 --get-signal-info :arrow_right: "Information unavailable"
  • uqmi -d /dev/cdc-wdm0 --get-imei :arrow_right: # Correct IMEI seems to have been found and logged here
  • uqmi -d /dev/cdc-wdm0 --get-capabilities :arrow_right:
{
    "max_tx_channel_rate": 150000000,
    "max_rx_channel_rate": 600000000,
    "data_service": "non_simultaneous_cs_ps",
    "sim": "supported",
    "networks": [
        "umts",
        "lte"
    ]
}