Sunday, April 6, 2014

I *finally* have RPi WiFi working (not easy with a hidden ssid)

woohoo!! ok, I've spent more time trying to get the WiFi working than anything else.

I tried everything... surely it is not difficult, considering how easy everything else was, no? No. The built-in WiFi configuration tool didn't not work for me. I found a cool WiFi tool called wicd. For more information see wifi on raspberry pi: a simple guide, at raspyfi.com (but it didn't work for my problem, either)

So the deal is: WiFi is easy to setup on RPi as long as the target AP has a ssid that is broadcasted. I prefer the security of an unbroadcasted ssid.  (details, details)

Google to the rescue! I found this awesome article on settig up the RPi as a WiFi radio. On the setup page, the author describes in detail how to setup WiFi with a hidden ssid.

We all know how over the years links change or simply go away, so I've copied the critical hidden ssid setup text from that article here (credit to Philip Burgess at adafruit):

Hidden Networks

If you run a hidden WiFi network — one that does not broadcast its SSID — this can still be made to work but is considerably more complicated. The slightest typo here, even one character, can prevent the system from joining the network! We strongly recommend using a “broadcast” network, it’s far easier and less error-prone.

sudo nano /etc/network/interfaces

Delete the {last} two lines {under "iface wlan0 inet dhcp" }   (wpa-ssid and wpa-psk) and replace with (indented):

pre-up wpa_supplicant -Dwext -i wlan0 -c /etc/wpa_supplicant/wpa_supplicant.conf -B

sudo nano /etc/wpa_supplicant/wpa_supplicant.conf

ctrl_interface=/var/run/wpa_supplicant
update_config=1
ap_scan=2
eapol_version=1
network={
 ssid="my-network-ssid"
 scan_ssid=1
 mode=0
 proto=WPA2
 auth_alg=OPEN
 pairwise=CCMP
 group=CCMP
 key_mgmt=WPA-PSK
 psk="my-network-password"
}
Replace ssid and psk with your actual network name and password, in quotes.

Important: indent the 'network' section using tabs, not spaces.
In the end, my \\raspberrypi\c$\etc\network\interfaces file looks like this:
auto lo

iface lo inet loopback
iface eth0 inet dhcp

auto wlan0
allow-hotplug wlan0
iface wlan0 inet dhcp
  pre-up wpa_supplicant -Dwext -i wlan0 -c /etc/wpa_supplicant/wpa_supplicant.conf -B

And my \\raspberrypi\c$\etc\wpa_supplicant\wpa_supplicant.conf file looks like this (with my ssid and psk where noted):

ctrl_interface=/var/run/wpa_supplicant
update_config=1
ap_scan=2
eapol_version=1
network={
 ssid="myssid"
 scan_ssid=1
 mode=0
 proto=WPA2
 auth_alg=OPEN
 pairwise=CCMP
 group=CCMP
 key_mgmt=WPA-PSK
 psk="mypsk"
}

Saturday, April 5, 2014

Hello World! (on my RPi)

so one of the reasons I bought my RPi was to build a syslog server. I found this raspihub article that basically says to install via:

apt-get install syslog-ng

I also have my first Hello World program working!  (plus samba & ssh working, in addition to xrdp)



Friday, April 4, 2014

My Rpi works! Ok, the initial display on my old tv was rather poor, but these settings via:

sudo nano /boot/config.txt

specifically adding:

hdmi_group=1
hdmi_mode=4

...ensures I am displaying hdmi in 720p (my old tv only displays 1024i = super blurry!)

For more information on forcing video modes, see the elinux RPi Config (video section)

I no longer need a keyboard and mouse attached to my RPi! I found this blog on how to setup RDP and now I can access my RPi from the comfort of my Windows 7 machine. <sigh of contentment>

Basically, to setup RDP, rum this command:

sudo apt-get install xrdp

(xwindows rdp, how cool is that!?)

For reference, I used this SD formatter to initialize my new SD card to install Raspian via the NOOBS installer (a simple copy to CD). Much more information on setup options can be found on the elinux "Easy CD Card Setup"

The RPi is ridiculously cool.  I've been out of the hardware world for way too long.

Wednesday, April 2, 2014


As I wait for my RaspPi to arrive, I've been reading more about Arduino. It looks rather interesting, and until recently - I didn't even know there was "open source hardware". (ok, clearly I've spent too much time in the software world). 

I'll plan to initially spend time seeing if I can get my Raspi to talk with a pile of opto22 devices that I have. That hardware use RS-485, so I bought this inexpensive USB to RS-485 adapter on amazon.com (one of the answered questions specifically noted this device works with the RasPi, I hope I can get it to work, too!)

When reading about the SD cards to use, apparently there was a problem in the past getting the UHS cards to work. It seems those issues have been resolved as noted on the elinux.org RPi SD cards site. For my RasPi, I ordered the SanDisk Ultra 8 GB SDHC Class 10 Flash Memory Card 30MB/s SDSDU-008G-U46 for less than $9, also from Amazon. (note the RPi specs say that no more than 20MB/s should be expected, so no sense in spending a ton of money on ultra-speed card). There's more performance information on the SD Card Benchmarks here.


Raspberry Pi is not the only kid on the block. Intel recently announced their latest Minnowboard and of course there's the beagleboard that seems to have been around for some time, too. I considered some of these, but the Raspberry Pi had the most appeal for its low cost and relatively large following. Some of the other embedded systems are probably great for more serious applications, like creating your own commercial DVR or something, but I was only interested as a hobbyist.

My Raspberry Pi is not here yet. Current status: "Out for delivery"

Raspberry Pi Ordered!

I ordered a new Raspberry Pi this week from amazon!

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