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NOTE: My board failed, had to send it back but more than a month later there's still no news. I contacted Antratek multiple times, but they just say they forwarded my requests to Olimex. Grr.

Disk Image

I got a problem with the disk image. Although it was a 4GB SD card, there was not enough space on the card to fit the image. This caused problems with the /var directory.

I dumped the card back to disk to verify

$ dd if=/dev/sdf of=/tmp/sdcard.img
$ ls -l /tmp/sdcard.img  a20_debian_kernel_3_4_LAN_USBx2_Cards_LCD_HDMI_SATA_TS_X_GPIO_OTG_MIC_release5.img 
-rw-r--r-- 1 hans hans 3980394496 Jan  4 21:44 a20_debian_kernel_3_4_LAN_USBx2_Cards_LCD_HDMI_SATA_TS_X_GPIO_OTG_MIC_release5.img
-rw-r--r-- 1 hans hans 3941597184 Jan  4 21:44 /tmp/sdcard.img

Clearly the sizes don't match. How to fix this? Well, the sdcard.img partition table is not correct, so delete the partition in the image and recreate it:

$ fdisk -u /tmp/sdcard.img

(delete (d) partition 2 and recreate it (n p), using the default parameters. The new partition will be a bit smaller. print the table (p) Then quit(q)).

You'll see that partition 2 starts at sector 34816. This way we know the offset for the loopback device (you need root):

# losetup /dev/loop0 /tmp/sdcard.img -o $((34816*512))
# losetup /dev/loop1 a20_debian_kernel_3_4_LAN_USBx2_Cards_LCD_HDMI_SATA_TS_X_GPIO_OTG_MIC_release5.img -o $((34816*512))

Format the new (correct) partition, copy the files, and write the image.

# mkfs.ext3 /dev/loop0
# mkdir /tmp/src /tmp/dest
# mount /dev/loop0 /tmp/dest
# mount /dev/loop1 /tmp/src
# cp -ar /tmp/src /tmp/dest
# umount /tmp/src /tmp/dest
# dd bs=4M if=/tmp/sdcard.img of=/dev/sdf
# sync

I found the info here


Currently looking at SPI support. Found this info that seems promising (haven't tested anything).