3G-IoT-A -- Some extra info for Linux users

PuceBaboon

   Here are links to a series of posts with some information on the 3G-IoT-A.  The comments from other readers are helpful, too:-

   Linux-from-Linux install woes (trying to install Linux onto the 3G from a Linux machine):-

             https://esp8266hints.wordpress.c ... heap-5-linux-board/

   Bit and pieces of useful info (this is a work-in-progress, so check back later, too):-

             https://esp8266hints.wordpress.c ... e-pi-3g-iot-a-info/

   Hope this helps others just a little bit.

davidalfa

I already knew your site, thanks a lot for your help!
OrangePi support is a shame, forums are terrible, there should be specific sections for each board!

Anyways, I'm attaching some issues I got and how to overcome them.


My board was unable to boot, all I got was a bootloop.
Checking the schematics I found the UART uses 1.8V! I verified this with a multimeter.
Why is this not mentioned anywhere? The majority of the USB-Serial converters output 3.3v!
If you connect a 3.3V adapter, it will inject current into the pin, going to the 1.8V power rail (Hopefully not burning anything) and causing a bootloop with this message:

[EMI] no flash ID match, no DRAM info match !
<ASSERT> mt_emi.c:line 1048 0
PL fatal error...
PL delay for Long Press Reboot
pl pmic powerkey Release
[PLFM] emergency download mode(timeout: 5s).
mtk_arch_reset at pre-loader!

A workaround is to connect a diode, so the TX can only pull current from the pin, not inject it:





Then it started working as it should.

davidalfa

I couldn't get wifi working with the supplied instructions.

- networking.service fails to start at boot, but I can scan the wireless network using nmcli.
- Adding the wireless config to /etc/networking/interfaces completely kills the interface.

I ended using nmcli for everything:

1. nmcli con add con-name MyWifi ifname wlan0 type wifi ssid MyWifi ` `ip4 192.168.0.11/24 gw4 192.168.0.1
   
2. nmcli con mod MyWifi ipv4.dns "192.168.0.1,8.8.8.8"
   
3. nmcli con modify MyWifi wifi-sec.key-mgmt wpa-psk
   
4. nmcli con modify MyWifi wifi-sec.psk MyWifiPassword
   
5. nmcli connection up MyWifi

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Explanation:

1. nmcli con add con-name CONNECTION_NAME ifname wlan0 type wifi ssid SSID_NAME ` `ip4 IP_ADDRESS/24 gw4 GATEWAY
   
2. nmcli con mod CONNECTION_NAME ipv4.dns "DNS1,DNS2"

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The settings will be stored, no need to do this again, it will connect at boot from now on.

davidalfa

Still, I was unable to ping, getting "Temporary Failure in Name Resolution" error.
Running systemd-resolve --status showed the DNS, but still no avail.
Checking the files, I found that /etc/resolv.conf was symlinked to /var/run/NetworkManager/resolv.conf.
I decided to delete the symlink and create the new file from scratch:

1. sudo rm /etc/resolv.conf
   
2. sudo echo -e "nameserver 8.8.8.8\n nameserver 8.8.4.4\n" > /etc/resolv.conf
   
3. sudo chown root:root /etc/resolv.conf

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Apply the settings:

1. sudo systemctl restart systemd-resolved.service

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Now it worked:

1. orangepi@orangepi3g-iot-A:~$ ping google.com
   
2. PING google.com (142.250.184.174) 56(84) bytes of data.
   
3. 64 bytes from mad07s23-in-f14.1e100.net (142.250.184.174): icmp_seq=1 ttl=118 time=15.9 ms
   
4. 64 bytes from mad07s23-in-f14.1e100.net (142.250.184.174): icmp_seq=2 ttl=118 time=17.9 ms

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Now fixing apt repositories. Debian archived stretch release, so sources.list need to be updated.

1. sudo nano /etc/apt/sources.list

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Delete everything, paste the following:

1. deb http://archive.debian.org/debian/ stretch main contrib non-free
   
2. #deb-src http://ftp2.cn.debian.org/debian stretch main contrib non-free
   
3. 
   
4. deb http://archive.debian.org/debian-security/ stretch/updates main contrib non-free
   
5. #deb-src http://archive.debian.org/debian-security/ stretch/updates main contrib non-free

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Press Control+X , then "Y" to save the file.
Now apt will work:

1. orangepi@orangepi3g-iot-A:~$ sudo apt update
   
2. Ign:1 http://archive.debian.org/debian stretch InRelease
   
3. Hit:2 http://archive.debian.org/debian-security stretch/updates InRelease
   
4. Hit:3 http://archive.debian.org/debian stretch Release
   
5. Reading package lists... Done
   
6. Building dependency tree
   
7. Reading state information... Done
   
8. 131 packages can be upgraded. Run 'apt list --upgradable' to see them.

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iam

Audio Library for Orange Pi 3G-IoT board (Linux)

https://github.com/olegk0/OrangePi3G_Audio