A "Hacking Embedded Linux Devices" wiki site?

I have done a bit of work trying to hack cheap consumer devices to run different software - NSLU2, mediaMVP, musicPal, edimax IP Cameras etc.   I have also had a look at 'off the shelf' single board computers like bifferboard.
Whenever I start I have the difficult learning curve of trying to remember how to set up a cross compiler, cross compile libraries and link them into new software.
I also think it would be useful to have a nice list of which devices have been successfully hacked and which ones are difficult.
I am thinking of setting up a site to collate such basic information, which could then link out to the more specific project sites.
Unless anyone knows of one already?

I think it would need a wiki to store most of the information, and an email discussion group.  I wonder how best to do it - there are google sites and google groups, wikispaces, pbworks.

Any suggestions on the best way to do this?

Inside the Edimax IC-3010WG IP Camera

I have just added my photos of the inside of the Edimax IC-3010WG IP camera to my web page: http://ic-3010wg.webhop.net.
If anyone knows what 'J1' is, I would like to know!

Inside the Edimax IC-3010WG IP Camera

I have just added my photos of the inside of the Edimax IC-3010WG IP camera to my web page: http://ic-3010wg.webhop.net.
If anyone knows what 'J1' is, I would like to know!

Edimax IC-3010 Firmware Modification

I just discovered the 'stats' facility in blogger.com and realised that the most read posts in my blog are the ones about the Edimax IC3010 wireless ip camera. People are also looking at my web pages about it (http://ic-3010wg.webhop.net).
This got me thinking about it again so I have had a poke around inside the case - I'll post some pictures at the weekend.
There is not much to see in side - there is a mini wireless card and a single board computer. I was hoping to see a USB port, but the nearest I can find is a four pin header that is likely to be one (or more of):
- USB Port
- Serial (RS232 ish) console
- JTAG interface

I'll have to find the main system-on-chip pin-outs to try to decide what it is.

The main thing I struggle with is getting into the firmware files - I think the choice if you want to hack a device is to either connect a serial line to the console to get access to the boot loader, or modify the firmware.   Modifying the firmware sounds simplest, but you run the risk of turning the device into a brick....

That is about where I got to in the summer of 2009.  I am just downloading the latest firmware and source code from edimax to try to de-code the firmware building utility.   While I was doing this, I discovered that someone has already done it - http://www.suborbital.org.uk/canofworms/index.php?/archives/3-Getting-telnet-access-on-an-Edimax-IC3010-webcam.html.   Well done to them!

Edimax IC-3010 Firmware Modification

I just discovered the 'stats' facility in blogger.com and realised that the most read posts in my blog are the ones about the Edimax IC3010 wireless ip camera. People are also looking at my web pages about it (http://ic-3010wg.webhop.net).
This got me thinking about it again so I have had a poke around inside the case - I'll post some pictures at the weekend.
There is not much to see in side - there is a mini wireless card and a single board computer. I was hoping to see a USB port, but the nearest I can find is a four pin header that is likely to be one (or more of):
- USB Port
- Serial (RS232 ish) console
- JTAG interface

I'll have to find the main system-on-chip pin-outs to try to decide what it is.

The main thing I struggle with is getting into the firmware files - I think the choice if you want to hack a device is to either connect a serial line to the console to get access to the boot loader, or modify the firmware.   Modifying the firmware sounds simplest, but you run the risk of turning the device into a brick....

That is about where I got to in the summer of 2009.  I am just downloading the latest firmware and source code from edimax to try to de-code the firmware building utility.   While I was doing this, I discovered that someone has already done it - http://www.suborbital.org.uk/canofworms/index.php?/archives/3-Getting-telnet-access-on-an-Edimax-IC3010-webcam.html.   Well done to them!

Progress with IP Camera Viewer

The Edimax IP Camera seems to work fairly well, but the video stream seems to get interrupted every now and again, which makes the player crash - vlc just hangs, and mplayer exits.
I decided that exiting was better so I have written a simple pyGTK front end for mplayer to play the screen. It also includes a wireless network link quality monitor to help understand why it is not working - it is here as 'bentv'.

Note that bentv uses a library that I have started work on (named ntpylib for want of a better name) - so far it only contains one class, 'prefs', which deals with saving and loading of simple key/value data from XML files. It includes a dialog box that GUI programs (such as bentv.py) can use to allow the user to edit the data. prefs.py and prefs.glade need copying or linking into the bentv directory to make it work - there is no clever installer!

Progress with IP Camera Viewer

The Edimax IP Camera seems to work fairly well, but the video stream seems to get interrupted every now and again, which makes the player crash - vlc just hangs, and mplayer exits.
I decided that exiting was better so I have written a simple pyGTK front end for mplayer to play the screen. It also includes a wireless network link quality monitor to help understand why it is not working - it is here as 'bentv'.

Note that bentv uses a library that I have started work on (named ntpylib for want of a better name) - so far it only contains one class, 'prefs', which deals with saving and loading of simple key/value data from XML files. It includes a dialog box that GUI programs (such as bentv.py) can use to allow the user to edit the data. prefs.py and prefs.glade need copying or linking into the bentv directory to make it work - there is no clever installer!

Embedded Linux Firmware Binary Files

I have always struggled to understand the format of the binary files that store the firmware upgrades.
They tend to be a mixture of some simple text labels, a kernel image and one or more mountable filesystems.
I have written a little script that goes through a file in a brute force (one byte at a time) way and attempts to mount it as various filesystem types (script stored here).
I used the information found by this script, and the source code provided by Edimax to work out some information about the internals of the IC-3010WG IP Camera - it is written up here.

Embedded Linux Firmware Binary Files

I have always struggled to understand the format of the binary files that store the firmware upgrades.
They tend to be a mixture of some simple text labels, a kernel image and one or more mountable filesystems.
I have written a little script that goes through a file in a brute force (one byte at a time) way and attempts to mount it as various filesystem types (script stored here).
I used the information found by this script, and the source code provided by Edimax to work out some information about the internals of the IC-3010WG IP Camera - it is written up here.

Practical Experience using the Edimax IP Camera

We were away on holiday last week so I got to try using the Edimax IP camera 'for real' as a monitor to keep an eye on our disabled son - known as 'BenTV-ng' (next generation) to distinguish it from 'BenTV' which was the old analogue system I used to use.

I gave up on using ad-hoc networking and instead took my wireless access point with me. This had the added advantage of improving the range of transmission because I could arrange for the access point to be between the camera and the computer. The computer I used was a Toshiba netbook running Ubuntu Linux.

The first thing I noticed was that when I powered everything up, nothing happened. At first I thought it was because the access point needed to see a wired connection as well as a wireless one, because when I connected the computer to it using a wire things started to work. I soon realised that the range was awful - it stopped working as soon as you were outside of his room. This turned out to be my fault because I had also switched on the analogue camera, which transmitted on the same frequency as the wireless network, so the noise level was huge. Things got better when I switched off the analogue camera.

At first everything appeared to work - vlc rtsp://admin:1234@bentv/ipcam.sdp played the video stream with sound.
I soon noticed that if the network got interrupted vlc froze, giving an apparently good picture, but no movement, which was no use to me. Instead I changed to mplayer - at least if that got into trouble it crashed and closed the video playback window so you knew something was wrong.

I set up a simple shell script that loops indefinitely starting mplayer then when mplayer exits it re-boots the ip camera, waits for 30 seconds and starts mplayer again.
This approach worked pretty well - the 30 second interruptions during the re-boot were not usually too troublesome.

We did find some problems when the video stream only worked for a few seconds before mplayer exited and the re-boot sequence started again, which was no good at all. The only way I found to cure this was to power off the camera all together - a software re-boot via the web interface did not cure it. I'll set up a little test at home now to see how long it takes to get into this state, and whether it makes a difference if you use wireless or wired networking.

The code to achieve this is stored at http://code.google.com/p/ntmisc/source/browse/bentv/.

The most up to date information I have on using this camera with linux can be found at http://ic-3010wg.webhop.net.

Practical Experience using the Edimax IP Camera

We were away on holiday last week so I got to try using the Edimax IP camera 'for real' as a monitor to keep an eye on our disabled son - known as 'BenTV-ng' (next generation) to distinguish it from 'BenTV' which was the old analogue system I used to use.

I gave up on using ad-hoc networking and instead took my wireless access point with me. This had the added advantage of improving the range of transmission because I could arrange for the access point to be between the camera and the computer. The computer I used was a Toshiba netbook running Ubuntu Linux.

The first thing I noticed was that when I powered everything up, nothing happened. At first I thought it was because the access point needed to see a wired connection as well as a wireless one, because when I connected the computer to it using a wire things started to work. I soon realised that the range was awful - it stopped working as soon as you were outside of his room. This turned out to be my fault because I had also switched on the analogue camera, which transmitted on the same frequency as the wireless network, so the noise level was huge. Things got better when I switched off the analogue camera.

At first everything appeared to work - vlc rtsp://admin:1234@bentv/ipcam.sdp played the video stream with sound.
I soon noticed that if the network got interrupted vlc froze, giving an apparently good picture, but no movement, which was no use to me. Instead I changed to mplayer - at least if that got into trouble it crashed and closed the video playback window so you knew something was wrong.

I set up a simple shell script that loops indefinitely starting mplayer then when mplayer exits it re-boots the ip camera, waits for 30 seconds and starts mplayer again.
This approach worked pretty well - the 30 second interruptions during the re-boot were not usually too troublesome.

We did find some problems when the video stream only worked for a few seconds before mplayer exited and the re-boot sequence started again, which was no good at all. The only way I found to cure this was to power off the camera all together - a software re-boot via the web interface did not cure it. I'll set up a little test at home now to see how long it takes to get into this state, and whether it makes a difference if you use wireless or wired networking.

The code to achieve this is stored at http://code.google.com/p/ntmisc/source/browse/bentv/.

The most up to date information I have on using this camera with linux can be found at http://ic-3010wg.webhop.net.

Ad-Hoc Wireless Network Troubles

Now that I have the Edimax IP Camera working I want it to connect to my Toshiba NB100 netbook computer as simply as possible - the idea is to use it when we are away on holiday so I don't want to have to set up a whole network with an access point etc. Instead I just want to set up an ad-hoc network between the computer and the IP Camera.
According to the instructions this should be easy - I tell the IP Camera to connect to an ad-hoc network called 'bentv', and then use NetworkManager in the Ubuntu desktop of the netbook to create the ad-hoc network.
This works fine on my main laptop, but fails on the netbook.
It turns out that NetworkManager is not capable of putting the wireless card into ad-hoc mode.
The work around was to have the script to start the VLC viewer shutdown network manager and set up the network manually as follows:

#!/bin/sh
/etc/init.d/NetworkManager stop
ifconfig ath1 down
wlanconfig ath1 destroy
wlanconfig ath1 create wlandev wifi0 wlanmode adhoc
iwconfig ath1 essid bentv
iwconfig ath1 channel 1
iwconfig ath1 192.168.1.35
iwconfig ath1 netmask 255.255.255.0
ifconfig ath1 up

vlc --fullscreen rtsp://192.168.1.17/ipcam.sdp

/etc/init.d/NetworkManager start

This is based on information I found here.
This seems to work, but the wireless networking is a bit iffy after the script exits - I might have to do the wlanconfig destroy bit again to put it into infrastructure mode.

Ad-Hoc Wireless Network Troubles

Now that I have the Edimax IP Camera working I want it to connect to my Toshiba NB100 netbook computer as simply as possible - the idea is to use it when we are away on holiday so I don't want to have to set up a whole network with an access point etc. Instead I just want to set up an ad-hoc network between the computer and the IP Camera.
According to the instructions this should be easy - I tell the IP Camera to connect to an ad-hoc network called 'bentv', and then use NetworkManager in the Ubuntu desktop of the netbook to create the ad-hoc network.
This works fine on my main laptop, but fails on the netbook.
It turns out that NetworkManager is not capable of putting the wireless card into ad-hoc mode.
The work around was to have the script to start the VLC viewer shutdown network manager and set up the network manually as follows:

#!/bin/sh
/etc/init.d/NetworkManager stop
ifconfig ath1 down
wlanconfig ath1 destroy
wlanconfig ath1 create wlandev wifi0 wlanmode adhoc
iwconfig ath1 essid bentv
iwconfig ath1 channel 1
iwconfig ath1 192.168.1.35
iwconfig ath1 netmask 255.255.255.0
ifconfig ath1 up

vlc --fullscreen rtsp://192.168.1.17/ipcam.sdp

/etc/init.d/NetworkManager start

This is based on information I found here.
This seems to work, but the wireless networking is a bit iffy after the script exits - I might have to do the wlanconfig destroy bit again to put it into infrastructure mode.

More on Edimax IP Camera

I think we're getting somewhere. Searching around for references to IP cameras and mplayer yielded this thread which suggested the following:

mkfifo fifo.mpeg4
wget -q http://admin:1234@192.168.1.117:4322 -Ofifo.mpeg4 &
mplayer -V -demuxer 35 fifo.mpeg4

This seems to work ok - there is a bit of a delay in the video, but probably ~0.1 sec, which is acceptable.
Progress!
Just need to get sound working now....

Well, I did a bit more hunting around in the camera web set-up and realised I had missed a section about RTSP. The default was for RTSP to be enabled on port 554 with a rtsp path of ipcam.sdp.
When I tried

mplayer rtsp://192.168.1.117:554/ipcam.sdp

I got pictures AND sound!
I had tried rtsp before, but had missed the ipcam.sdp bit. Mplayer complains that my little netbook is too slow to play the stream, so there is a bit more work to do, but it looks promising. I'll try VLC now.

The most up to date information I have on using this camera with linux can be found at http://ic-3010wg.webhop.net.

More on Edimax IP Camera

I think we're getting somewhere. Searching around for references to IP cameras and mplayer yielded this thread which suggested the following:

mkfifo fifo.mpeg4
wget -q http://admin:1234@192.168.1.117:4322 -Ofifo.mpeg4 &
mplayer -V -demuxer 35 fifo.mpeg4

This seems to work ok - there is a bit of a delay in the video, but probably ~0.1 sec, which is acceptable.
Progress!
Just need to get sound working now....

Well, I did a bit more hunting around in the camera web set-up and realised I had missed a section about RTSP. The default was for RTSP to be enabled on port 554 with a rtsp path of ipcam.sdp.
When I tried

mplayer rtsp://192.168.1.117:554/ipcam.sdp

I got pictures AND sound!
I had tried rtsp before, but had missed the ipcam.sdp bit. Mplayer complains that my little netbook is too slow to play the stream, so there is a bit more work to do, but it looks promising. I'll try VLC now.

The most up to date information I have on using this camera with linux can be found at http://ic-3010wg.webhop.net.

Edimax IC-3010Wg again

I have made a bit more progress getting my Edimax IP Camera working, and detailed what I have learned at http://ic-3010wg.webhop.net.

The main problems are still that although I can download an MPEG4 stream using wget, neither mplayer nor vlc will play it directly, which is no good.
The other issue is that sound still does not work.....

Edimax IC-3010Wg again

I have made a bit more progress getting my Edimax IP Camera working, and detailed what I have learned at http://ic-3010wg.webhop.net.

The main problems are still that although I can download an MPEG4 stream using wget, neither mplayer nor vlc will play it directly, which is no good.
The other issue is that sound still does not work.....

Edimax IC-3010Wg IP Camera and Linux

I have just got an Edimax IC-3010Wg IP Camera. I intend to use it as a replacement for the analogue video system we use to keep an eye on our disabled son.
I was rather disappointed to find that it does not work with Firefox - you need an Internet Explorer ActiveX control to view the video images. This means it will not work on my Linux computers as supplied by the manufacturer.

What works:

1. The camera gets its network configuration by DHCP (despite what the quick start guide says) so by checking the DHCP deamon log you can find its IP address.
2. You can access its configuration screen with a web browser (default username admin, password 1234)
3. Receive a snapshot picture using http:///snapshot.jpg
4. Download a mjpeg video stream using wget http://admin:1234@192.168.1.117/mjpg/video.mjpg. (I don't know how to display this in real time though - mplayer doesn't seem to work).
5. Some other things are detailed here.
6. Someone has written a tcl application that works with a similar camera, but not this one (see here).

I think I am going to end up writing something based on the tcl application shown above to display live video with sound, which is what I need. If anyone knows an off-the shelf one, please let me know!

The most up to date information I have on using this camera with linux can be found at http://ic-3010wg.webhop.net.

Edimax IC-3010Wg IP Camera and Linux

I have just got an Edimax IC-3010Wg IP Camera. I intend to use it as a replacement for the analogue video system we use to keep an eye on our disabled son.
I was rather disappointed to find that it does not work with Firefox - you need an Internet Explorer ActiveX control to view the video images. This means it will not work on my Linux computers as supplied by the manufacturer.

What works:

1. The camera gets its network configuration by DHCP (despite what the quick start guide says) so by checking the DHCP deamon log you can find its IP address.
2. You can access its configuration screen with a web browser (default username admin, password 1234)
3. Receive a snapshot picture using http:///snapshot.jpg
4. Download a mjpeg video stream using wget http://admin:1234@192.168.1.117/mjpg/video.mjpg. (I don't know how to display this in real time though - mplayer doesn't seem to work).
5. Some other things are detailed here.
6. Someone has written a tcl application that works with a similar camera, but not this one (see here).

I think I am going to end up writing something based on the tcl application shown above to display live video with sound, which is what I need. If anyone knows an off-the shelf one, please let me know!

The most up to date information I have on using this camera with linux can be found at http://ic-3010wg.webhop.net.