Arietta technical documentation

Getting started with Arietta G25

Fist steps to get started with Arietta G25 Linux board

What do you need to start

  • A micro SD Card of 4,8,16 or 32 GByte class 4 or higher preinstalled with Debian Linux or Buildroot.
  • A micro USB data cable used to link Arietta with your PC. In that way Arietta emulates a LAN adapter and will be visible via web or ssh.
  • A Linux or Microsoft Windows PC. We wrote this tutorial using an Ubuntu Linux 15.04 and Windows 7 some little differeces may happen on other environments.

Not required stuff but very useful to have

  • An Internet connection To update or download software, we recommend that you connect your PC to the internet either via and ethernet cable or a wifi adapter. Arietta without the WiFi adapter can use your PC as a gateway to have access to the Debian packages repositories.
  • A debug port interface interface This is just a TTL@3V3 level serial interface to get access at the Arietta debug port. It is very useful to see what the board is doing in any moment. You can buy our DPI interface or any third party 3V3 serial interface. Be carefull at the voltage levels. Any signal higher than 3.3 volt will damage the board.
    Debug Port Interfaces:
  • A 5 Volt DC power supply You need a power supply only when you are using the Arietta in stand alone mode o with a WiFi or Ethernet adapter. Be careful that whatever power supply you use outputs at least 5V; insufficient power will cause your Arietta to behave in strange ways. The power con be provided via the micro usb connector or via the J4 pads.

Step by step procedure

Slotting the bootable Linux microSD card into the card slot
Plug the micro usb cable to Arietta and to a PC host port. This action will turn on and boot up the board.
The led on-board will blink after a while to indicate that the Linux Kernel is running.

PC network configuraton

When you plug the Arietta board to your PC USB port it just detects Arietta as a new lan adapter but some manual setup are
required to have access to the Linux command prompt, web server etc. and to allow to Arietta to reach Internet using you PC as a gateway.

Linux Ubuntu network configuration

Edit the /etc/network/interfaces file on your Linux PC using the root privileges:

$ sudoedit /etc/network/interfaces

and add these lines:

allow-hotplug usb0
iface usb0 inet static
    address 192.168.10.20
    netmask 255.255.255.0

Plug Arietta and check dmesg until you see these lines:

$ dmesg
usb 1-1: new high-speed USB device number 14 using ehci-pci
usb 1-1: New USB device found, idVendor=0525, idProduct=a4a2
usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=0
usb 1-1: Product: RNDIS/Ethernet Gadget
usb 1-1: Manufacturer: Linux 3.14.7+ with atmel_usba_udc
cdc_eem 1-1:1.0 usb0: register 'cdc_eem' at usb-0000:00:1d.7-1,
CDC EEM Device, b2:2b:7d:e0:45:8e

If you use:

$ watch "dmesg | tail -20"

the last 20 lines on dmesg will be refreshed automatically on your terminal.

At this point, if everything is going well, a new interface called usb0 with IP address 192.168.10.20 appear typing:

$ ifconfig
usb0      Link encap:Ethernet  HWaddr b2:2b:7d:e0:45:8e  
          inet addr:192.168.10.20  Bcast:192.168.10.255  Mask:255.255.255.0
          inet6 addr: fe80::b02b:7dff:fee0:458e/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:37 errors:0 dropped:0 overruns:0 frame:0
          TX packets:55 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:5810 (5.8 KB)  TX bytes:9823 (9.8 KB)

If not try to bring up the interface by typing:

$ sudo ifup usb0

When usb0 is try to ping Arietta using its statically IP address 192.168.10.10:

$ ping 192.168.10.10
PING 192.168.10.10 (192.168.10.10) 56(84) bytes of data.
64 bytes from 192.168.10.10: icmp_seq=1 ttl=64 time=1.43 ms
64 bytes from 192.168.10.10: icmp_seq=2 ttl=64 time=1.54 ms

or its bonjour name:

$ ping arietta.local
PING arietta.local (192.168.10.10) 56(84) bytes of data.
64 bytes from arietta.local (192.168.10.10): icmp_seq=1 ttl=64 time=0.574 ms
64 bytes from arietta.local (192.168.10.10): icmp_seq=2 ttl=64 time=0.586 ms

Share the Internet link of your PC

To let Arietta to get the access to the Internet link of your Linux PC type on your Ubuntu PC:

~$ su
Password: *******
# iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
# echo 1 > /proc/sys/net/ipv4/ip_forward
# exit
exit
~$ 

Add a DNS IP inside /etc/resolv.conf on Arietta and try to ping an Internet server:

root@arietta:~# echo "nameserver 8.8.8.8" > /etc/resolv.conf
root@arietta:~# ping www.acmesystems.it
PING www.acmesystems.it (78.47.10.198) 56(84) bytes of data.
64 bytes from static.198.10.47.78.clients.your-server.de (78.47.10.198): icmp_req=1 ttl=127 time=94.1 ms
...

Windows 7 network configuration

Enable Windows to download the drivers from Windows Update as shown on this video:


Plug Arietta on an USB port on your PC and check on the Control Panel the new network adapter called USB Ethernet/RNDIS Gadget.

After the driver installation open the Control Panel and click on "Hardware and Sounds":

Click on "Device manager":

and see the new adapter name:

Assign a static IP address to the new adapter

From the control panel select "Network and Internet":

Then click on "Network and Sharing Center":

Click on "Change adapter settings":

Right-click on the new adapter USB Ethernet/RNDIS Gadget and select Properties menu item:

Click on Internet Protocol Version 4 and on the Properties button.

Insert:

  • IP address: 192.168.10.20
  • Subnet mask: 255.255.255.0

Save pressing on the OK button.

Now open your Internet Explorer and go to the url http://192.168.10.10 to see the Arietta Web Page.

Getting access to Arietta

Now it is possible to get access to your Arietta via using its address 192.168.10.10 in these ways:

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

Arietta technical documentation