Thursday, February 28, 2013

Rpi on the Network

As mentioned in the previous post, I now have my Raspberry PI (Rpi) connected to the Network, serving Web Pages and providing (my) access via SSH and Remote Desktop.

Only one wire is needed for this configuration, that is the 5 Volt power from a 1 Amp wall wart. Network access is via the USB WiFi Adapter as shown in the photo. This Rpi can be accessed from anywhere in the world as http://Rpi.WA0UWH.com:8040 . Currently it is serving only a single web page, other fun pages (or links) will be added later.
Rpi running a Web Server, SSH, and Remote Desktop
http://Rpi.WA0UWH.com:8040
My plans include connecting the Rpi to an Ensemble Receiver (SDR), which can be done with only the addition of an Antenna and USB Sound Card.

I am considering moving the Rpi and the SDR to a remote location (where I have WiFi access) so that I can Transmit from my Shack, without overloading the SDR. This remote location will be good for remote QRSS Grabber operation.

I am impressed with the Rpi, it is a fun system.


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Thursday, February 21, 2013

A Piece of the PI

Several days ago, I received an e-mail from Adafruit informing that they had Raspberry PI boards available, I had been on their waiting list for several weeks. Once ordered it was only a few days before the PI arrived - yesterday.

I spent several hours reading the "Getting Started" web information pages. I did not purchase a pre-loaded SD card as I have several.

Some Lessons learned
  • The micro USB connector is only used for power (+5V).
  • It is difficult to use the PI if you do not have a HDMI display, but it is possible to run the PI without a display, but when first starting and not knowing what to expect, it was difficult to know that it was actually working (or NOT). Now I know that the 5 LEDs blink and flash when booting. Initially I had a bad SD card and nothing was working. A working PI boots in about 30 seconds with all LEDs flashing.
  • Thanks to information found on the web, a static address can be forced (for easy access via SSH), by editing the "/etc/network/interfaces" while the SD card is mounted on another system, I used 192.168.2.40
Orignial file: /etc/network/interfaces

auto lo

iface lo inet loopback

iface eth0 inet dhcp

allow-hotplug wlan0
iface wlan0 inet manual
wpa-roam /etc/wpa_supplicant/wpa_supplicant.conf
iface default inet dhcp


File changed to:

auto lo

iface lo inet loopback

#iface eth0 inet dhcp

auto eth0
iface eth0 inet static
address 192.168.2.40
netmask 255.255.255.0
gateway 192.168.2.1
dns-nameservers 192.168.2.1

allow-hotplug wlan0
iface wlan0 inet manual
wpa-roam /etc/wpa_supplicant/wpa_supplicant.conf
iface default inet dhcp


Soon, I will replace the Ethernet cable with a WI-FI adapter, and replace the Micro USB +5V supply connection with a battery. I will then have a stand-alone portable networked system. I will probable only use SSH, VNC, and remote X11 windows to access the PI.

I think I will like the PI, it boots fast and with an USB audio adapter it will be useful for my Ham Radio adventures with SDR and other radio controls.


UPDATE - Feb 21, 2013
With the following command, I installed "fldigi"
  • aptitude install fldigi
I do not have a USB sound adapter installed yet, but "fldigi" runs with my minimal configuration!

I need to get a stand-alone USB wall wart to power the PI (or a battery) and a USB expander to connect other USB devices (i.e., sound adapter), the PI has only a minimal amount of current it can supply to external USB devices. Other web doc's suggests a powered USB Expander is required.


UPDATE - Feb 22, 2013
I returned the "/etc/network/interfaces" file to original configuration, and then modified my home router config to serve my desired IP Address for the PI's MAC address via DHCP. The advantage here is the PI will have a known IP Address while on my Network, but will obtain any an available DHCP IP Address when at any other location.


UPDATE - Feb 25, 2013
I now have the PI serving web pages, as: http://Rpi.WA0UWH.com:8040


UPDATE - Feb 27, 2013
My PI is now using an WiFi connection to the network, only the single power connection wire is connected to the PI. The power cord could be replaced with a Battery for a completely portable PI web server.

I used information found at: http://www.raspberrypi.org/phpBB3/viewtopic.php?f=26&t=26795. The only difference is that I set up to use a Static IP Address as configured and served via DHCP from my WiFi Router.


UPDATE - Mar 10, 2013

Sometime today my Rpi died, not sure why, but I will not have time to fix/rebuild it until later this week. At last count it had served a connection for 213 users via web requests.

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