WIFI-2 - OEM WiFi USB module (RaLink RT5370N)

WIFI-2 is an USB 2.0 module compliant with IEEE802.11 b/g/n. It is based on a RaLink RT5370N chip and fully supported by the latest Kernel Linux versions. It can be mounted directly on a PCB instead of plugged in a USB port and works at 3.3 Volt. It can work in managed, ad-hoc and access point mode.

This module is available in two versions:

  • WIFI-2 which needs an external RF antenna plugged on the i-PEX MHF receptacle
  • WIFI-2-IA without the i-PEX MHF receptacle using the onboard PCB antenna

Both models are available with a 6 pin pitch 2mm solded on semi-holes to be plugged on a female connector or welded directly on the PCB.





  • WIFI-2 pinout

    Pin # Signal Description
    1 TX RF ON/OFF control. Low=OFF. Pull-up to 3V3 with an external 4.7K resistor
    2 3V3 Power supply 3.3 VDC
    3 D- USB data -
    4 D+ USB data +
    5 GND Ground
    6 LED Module working status led output
    7 WPS WPS function. Low level activated

Linux Kernel configuration

This are the driver to enable inside the Linux Kernel to support wifi module. Follow these articles to know how to compile the Linux kernel:

To change the Kernel configuration use this command on your Linux PC as described on this article:

make ARCH=arm menuconfig

Thanks set these items:

Device Drivers  --->
  [*] USB support  ---> 
    <*> USB Wireless Device Management support

and these:

Device Drivers > 
  Network device support > 
    Wireless LAN [*]
     [*]   Ralink devices
     <*>   Ralink driver support --->

and then:

--- Ralink driver support
< >   Ralink rt2500 (USB) support
< >   Ralink rt2501/rt73 (USB) support
<*>   Ralink rt27xx/rt28xx/rt30xx (USB) support
[ ]     rt2800usb - Include support for rt33xx devices
[ ]     rt2800usb - Include support for rt35xx devices (EXPERIMENTAL)
[ ]     rt2800usb - Include support for rt3573 devices (EXPERIMENTAL)
[*]     rt2800usb - Include support for rt53xx devices (EXPERIMENTAL)
[ ]     rt2800usb - Include support for rt55xx devices (EXPERIMENTAL)
[ ]     rt2800usb - Include support for unknown (USB) devices
[ ]   Ralink debug output

Package installation

A closed firmware made by RaLink need to be installed. This firmware will be loaded on the module at startup

Change this line in /etc/apt/sources.list

deb http://cdn.debian.net/debian/ buster main


deb http://cdn.debian.net/debian/ buster main contrib non-free

then update the package index by typing

sudo apt update
sudo apt install firmware-ralink

Install iw and wpasupplicant using make menuconfig:

sudo apt install wpasupplicant
sudo apt install iw

Network configuration to get access to a WPA-WPA2-protected Wi-Fi

Add, inside the directory /etc/network/interfaces.d a file called wlan0 by typing:

sudo nano /etc/network/interfaces.d/wlan0

Write these lines and save:

allow-hotplug wlan0
iface wlan0 inet dhcp
    wireless-essid any
    pre-up wpa_supplicant -i wlan0 -c /etc/wpa_supplicant/wpa_supplicant.conf -B
    post-down killall -q wpa_supplicant

Create a file called /etc/wpa_supplicant.conf that contains your access point name and password.

sudo nano /etc/wpa_supplicant/wpa_supplicant.conf

Write these lines and save:



Alternatively it is possible to hide the password using wpa_phassphrase by typing:

wpa_passphrase acmetest acmetest



Restart wlan0 with these command or reboot:

sudo ifdown wlan0
sudo ifup wlan0

After a while if the dhcp are working well you will obtain your interface up.

Wi-fi adapters

Sergio Tanzilli
Systems designer, webmaster of www.acmesystems.it and founder of Acme Systems srl

Personal email: tanzilli@acmesystems.it
Web pages: https://www.acmesystems.it --- https://www.acmestudio.it
Github repositories: https://github.com/tanzilli --- https://github.com/acmesystems
Telegram group dedicated to the Acme Systems boards: https://t.me/acmesystemssrl