Kontron pITX-SP - Manual (Page 19)

KTD-S0003-C Page 15 SDIO/microSD Card Interface
p ITX-SP Software Guide
5 SDIO/microSD Card Interface
The following operating systems allow booting from SDIO/microSD cards: DOS, Linux, Windows ® XP/
Windows ® 7 and Windows ® XP Embedded.
5.1 DOS Boot
All standard DOS programs for partitioning and formating can be used (e.g. FDISK.EXE and FORMAT.COM).
However it can not be guaranteed that all functions of INT13h respectively INT21h work correctly. Fol-
lowing steps are necessary to prepare a DOS bootable card.
❶ Partitioning and formating the SDIO/microSD card.
❷ Use the 'HP USB Disk Storage Format Tool' or an other program and a USB Card Reader with
SD/MMC support on a host computer to make the card bootable.
The table shows a list of the tested DOS versions.
Operating System Version Result
MS-DOS 6.22 ✔
MS-DOS WIN 98 (7.10) ✔
DR-DOS 7.03 ✔
5.2 Linux Boot
To successfully boot Linux from an SDIO/microSD card use a kernel version >= 2.6.29 . Following changes
are necessary:
❶ In the kernel configuration please make sure that under
Device Drivers
MMC/SD/SDIO card support
MMC block device driver ,
Secure Digital Host Controller Interface support and
SDHCI support on PCI bus are enabled.
Please set them to be built into the kernel unless you know how to deal with modules required
for boot devices.
❷ For the kernel parameters in the bootloader configuration file please use
/dev/mmcblk0p1
as your root device (MMC block device 0 partition 1, adjust to fit your setup). Moreover it is
required to tell the kernel to wait some more time before mounting the root device, since
depending on the SD card model it may take up to several seconds until the device is ready. To
do this use
rootdelay = xx
on the parameter line. An example line for grub with a system installed on disk 1 partition 1,
no separate boot partition and a quite slow card that requires 10 seconds delay could look like
this
kernel vmlinuz root = /dev/mmcblk0p1 rootdelay = 10 .