NOTE: Read the whole guide before doing any steps from this guide to make sure you understand everything.
If you do not want to erase the NAND partition or the internal 32G eMMC from the N900 device, this installation is for you. What you need for this installation is a raw image that can be put to the MMC card and kernel (same kernel that is installed to the MMC).
First what you need is a microSD memory card which does not contain any information that you need as it will be erased during this operation.
The steps in this guide require an MMC card of at least 2gb however some cards offer slight variations in capacity, so better to take a 4gb card to be on the safe side :)
When inserting the microSD memory card in the card reader you need to find out the proper device for the card. This can be done with for example fdisk:
sudo fdisk -l
An example output (NOTE: The /dev/sdX is used as an example on your PC this might be also called /dev/mmcblk0, /dev/sdd or something else)
$ sudo fdisk -l ... Disk /dev/sdX: 3965 MB, 3965714432 bytes 194 heads, 30 sectors/track, 1330 cylinders Units = cylinders of 5820 * 512 = 2979840 bytes Disk identifier: 0x0001ab40 Device Boot Start End Blocks Id System /dev/sdX1 1 588 1708984 83 Linux
NOTE: The .raw image contains the partition table as well. So the image needs to be written to /dev/sdX not /dev/sdX1.
After you are 100% sure that the /dev/sdX is the microSD memory card you just inserted in the card reader you can use for example dd to put the image to the card:
$ sudo dd bs=4096 if=<raw_image> of=/dev/sdX 448000+1 records in 448000+1 records out 1835008001 bytes (1.8 GB) copied, 300.641 s, 6.1 MB/s
The dd does not show any progress until the file is written to the device so be patient.
After this you can insert the card in the N900.
This should be a last resort solution.
sudo gainroot umount /dev/mmcblkXpY dd if=/home/user/MyDocs/meego-image.raw of=/dev/mmcblk1
for detailed information.
NOTE: Back cover must be closed to boot from MMC.
NOTE: If you have a flashing jig, you will need to put a magnet at the red location marked here
Before the MeeGo is able to boot you need also load the kernel (vmlinuz) provided with the raw image to the device. This can be done with the flasher
$ sudo flasher-3.5 -l -b -k <kernel>
NOTE: The command above will only load the kernel to the device, so next time you boot the device the original kernel should be used and your Maemo 5 OS should boot normally.
If you want to flash the kernel to your device so that it is not forgotten when it is powered off use option -f instead of option -l on command above.