Setup Wi-Fi on Maivin

This article describes how to enable Wi-Fi for wireless communications on Maivin.  

Prerequisites

In order to use Wi-Fi on Maivin, at least 1 antenna must be connected to the SOM module, and the SOM module must have the Wi-Fi module option.

Toradex Module Wi-Fi accessory recommendations

Antennas

Two options for antennas are available.  Either use an internal flex circuit style antenna placed on the inside of the enclosure, or a cable with SMA connector for a dipole antenna connected to the rear of the enclosure.  Antennas may be ordered from Au-Zone Web Store, or order a Maivin with pre-installed antennas.

Internal Antenna Options:

• Unictron H2B1PD1A1C385L

• Molex 1461531100

External Antenna Options:

• MHF4 to RP-SMA cable 150mm to 200mm long.
  • eg. PulseLarsen Antennas - W9037BD0100
  • 
• RP-SMA dipole antenna
  • eg. Chang Hong DA-2458-02
  • 

Installing Antennas

The antennas are connected directly to the Wi-Fi module on the Verdin SOM module.  The unit must be disassembled to access the Wi-Fi antenna connectors on the SOM.  There are 2 antenna connectors that can be used to connect up to 2 antennas to provide antenna diversity to improve Wi-Fi performance.  

Disassemble Maivin Camera

1. Remove the bottom cover by first removing the 4 x M2.5 enclosure screws using the 1.5mm Hex key.  Carefully lift off the rear cover, while leaving the internal boards installed in the top enclosure.
2. Unscrew the carrier board from the top enclosure by removing the 4 x M2 screws using the 1mm Hex Key.
3. Carefully remove the carrier board and attached rear connector board and image sensor board from the enclosure.

Internal Antenna Installation

The internal flex circuit antennas have adhesive on the backs to allow them to be fastened to the inside of the enclosure.  Carefully remove the adhesive backing and firmly press the antenna into the enclosure internal wall to mount the antenna.  Carefully route the cable back to the SOM module for installation.  Ensure the routing of the cable does not have any sharp bends in the cable.  Installation of the antenna onto the side of the enclosure provides easy routing of the antenna cable.

External Antenna Installation

The Maivin kit comes with an alternate rear cover with a hole.  This hole is used to mount the RP-SMA connector to allow connection of the external antenna.  Fasten the RP-SMA connector using the washer and nut as supplied with the cable.  Route the cable past the opening in the rear connector board and to the SOM antenna connectors.

A Dipole antenna can be screwed into the RP-SMA.

Connect the Antenna to the Wi-Fi Module

1. Remove the heatsink from on top of the SOM board.  Using a philips screwdriver, remove the 4xM2 screws.  The heatsink can be gently lifted off the SOM module.  Be sure to pull straight on the heatsink as there is a thermal interface pad between the heatsink and SOM board that needs to stay in place.  Once the heatsink is removed, the antenna connectors can be accessed.
2. Plug in the antenna cable to the MHF4 connectors on the module.  If using only one antenna, only connect one.

Re-assemble the Camera

Reverse the above steps to reassemble the unit.

1. Install the heatsink back onto the Carrier board and SOM.  Note, the heatsink will cover the antenna connectors.
2. Place the carrier board into the top enclosure and fasten with the 4 - M2x5mm screws.
3. Re-install the rear carrier board and image sensor boards into the slots in the top enclosure.
4. Verify the routing of the antenna cables are not pinched or kinked in any way.
5. Re-install the rear enclosure onto the unit and fasten with the 4 M2.5 enclosure screws.

How to Configure Wi-Fi on the Maivin OS

For information on how to connect to the command-line interface of the Maivin, please view this article.  Prior to setting up the Maivin Wi-Fi client, please disable the uap0 interface with the following commands:

echo -e "[keyfile]\nunmanaged-devices=interface-name:uap0" | sudo tee /etc/NetworkManager/conf.d/99-unmanaged-uap0.conf
sudo systemctl restart NetworkManager

By doing those steps, the list of NetworkManager managed devices should change from from:

torizon@verdin-imx8mp-15141027:~$ nmcli -c no d
DEVICE TYPE STATE CONNECTION
ethernet0 ethernet connected network0
mlan0 wifi disconnected --
uap0 wifi disconnected --
docker0 bridge unmanaged --
can0 can unmanaged --
sit0 iptunnel unmanaged --
lo loopback unmanaged --

to

torizon@verdin-imx8mp-15141027:~$ nmcli -c no d
DEVICE TYPE STATE CONNECTION
ethernet0 ethernet connected network0
mlan0 wifi disconnected --
docker0 bridge unmanaged --
can0 can unmanaged --
sit0 iptunnel unmanaged --
lo loopback unmanaged --
uap0 wifi unmanaged --

After this step, please follow this article on how to setup Wi-Fi on Torizon.  Refer to Toradex Verdin Wi-Fi Documentation for certifications related to the Wi-Fi Module.

NOTE: If the nmcli output formatting is incorrect, use the "-c no" no colours command-line option or set the NO_COLOR=1 environment variable on the Maivin to disable the ANSI colour codes in the NetworkManager output.