HOWTO: Set up a Maemo 5 Scratchbox SDK VM (and upload packages)

I've somehow lost my good old "MaemoSDK" VirtualBox VM, so while I'm setting up the new VM, here are the instructions in case I or somebody else needs to do that again.

The goal: To have a nice VM (more lightweight than the Maemo SDK VMs offered online) that one can SSH into and build packages for Maemo 4 and Maemo 5:

1. Get the Debian i386 netinst CD image from http://www.debian.org/CD/netinst/
2. Create a new VirtualBox VM (Name: MaemoSDK, Operating System: Linux, Version: Debian) - the default size (8 GB) should be okay, less is also okay
3. Go to Settings, Storage, IDE Controller, select the .iso you downloaded in step 1
4. Power up the VM, select "Install" in the menu
5. Set the hostname to "maemosdk"
6. Use an empty root password (you can use "sudo" from your user)
7. Full name for the new user: Maemo Developer
8. Username for the new user: user
9. Password for the new user: maemo
10. Use the default options for partitioning, and wait until the base system is installed
11. Select the "SSH Server" option when the Debian Installer offers it
12. Install GRUB into the MBR of the VM
13. Go to the Maemo 5 SDK Download Page on Nokia Developer
14. From the SDK Download page, get the Scratchbox installer script (maemo-scratchbox-install_5.0.sh) and the SDK installer script (maemo-sdk-install_5.0.sh):

    http://repository.maemo.org/stable/5.0/maemo-scratchbox-install_5.0.sh

    http://repository.maemo.org/stable/5.0/maemo-sdk-install_5.0.sh 

15. Login to your new VM, then wget the two scripts above
16. sudo sh maemo-scratchbox-install_5.0.sh
17. sudo sh maemo-scratchbox-install_5.0.sh -u user
18. Log out and log back in again
19. sh maemo-sdk-install_5.0.sh
20. When asked, I chose Full + Development packages, but feel free to chose a more minimal variant (in that case, you might have to install -dev packages later on as build-dependencies)

You can also read up on how to set up SSH agent forwarding in the VM, so that you don't need to store your SSH key on the SDK VM.

As for building gPodder from source in this SDK, here are the instructions:

1. scratchbox
2. vi /etc/apt/sources.list # then add these entries:
   deb http://repository.maemo.org/extras-devel fremantle free non-free
   deb-src http://repository.maemo.org/extras-devel fremantle free
3. fakeroot apt-get install python2.5 python-feedparser python-mygpoclient python-dev maemo-optify
4. git clone git://github.com/gpodder/gpodder.git
5. cd gpodder
6. git checkout origin/maemo-5
7. dpkg-buildpackage -rfakeroot -S -sa -I.git -i.git # for the source upload
8. dpkg-buildpackage -rfakeroot -b # for the binary to test locally

You can also build the Maemo 4 (N800/N810) package by replacing "maemo-5" with "maemo-4" in the "git checkout" command.

To get files out of the SDK without setting up fancy SSH stuff, you can also just use netcat (on the target: nc -l 9999 | tar xzv, on the source: tar czv /path/to/files/ | nc a.b.c.d 9999).

To upload files to Maemo Extras, follow the instructions at Uploading to Extras.

Charging a BL-5J (N900) battery in the N810

There are several reasons why you would like to charge your N900 battery in a N810. Maybe you have a spare battery that you want to charge while using the other battery in your N900, or maybe your N900 refuses to charge the battery by itself. Please note that even though it works for me, the standard disclaimer applies - it's all your fault if this destroys your devices and/or batteries :)

Now, let's have a look at the pinouts and connectors of both batteries:

So, the connectors seem to have the same size, even though the batteries do not. Trying to put the N900 battery into the N810 is not straightforward, as there is a white piece of plastic that prevents the battery from getting close to the connectors. The solution is to simply use the N810 stylus as a lever to push the battery towards the connectors:

After the stylus and battery are fixed, simply connect the N810 to the power adapter, and it should start charging. Thanks to Quim for this helpful hint :)

HOWTO: Stable Xephyr on Ubuntu 9.04 for Fremantle SDK

As stated in the Fremantle SDK Installation Notes, Xephyr on Ubuntu 9.04 crashes when clicking on a text field in the Fremantle Beta SDK. It also says that the Intrepid (Ubuntu 8.10) version works better. Here is how you can compile and install Intrepid's Xephyr version:

sudo apt-get build-dep xserver-xephyr
sudo apt-get install build-essential devscripts
dget http://at.archive.ubuntu.com/ubuntu/pool/main/x/xorg-server/xorg-server_1.5.2-2ubuntu3.dsc
dpkg-source -x xorg-server_1.5.2-2ubuntu3.dsc
cd xorg-server-1.5.2/
debuild
cd ..
sudo dpkg -i xserver-xephyr_1.5.2-2ubuntu3_i386.deb
Xephyr :2 -host-cursor -screen 800x480x16 -dpi 96 -ac &

Now you can start the Fremantle Beta SDK and run it without crashing all the time :) You can delete the rest of the .deb packages created - they are not needed for Xephyr. If you want to go back (well... "forward" really) to Jaunty's Xephyr package, you can simply use sudo aptitude install xserver-xephyr to upgrade it.