Creating a bootable microSD card
The Overo board will boot directly from a properly prepared microSD card. This section will outline how to partition and format a bootable microSD card. In order to create a bootable microSD compatible with the OMAP3 boot ROM, the SDK automatically format the SD and save the necessary images in the correct partitions.
This example will show the steps for setting up a 2GB microSD card.
Verify your SD CARD is working
First insert your card into your development machine's flash card slot. You may need to use a microSD to SD card adaptor to fit your slot. You can use 'mount' or 'df' to see where the card mounts on your machine.
$ df Filesystem 1K-blocks Used Available Use% Mounted on /dev/sda1 234521212 35058568 187549648 16% / none 1009920 372 1009548 1% /dev none 1014140 1940 1012200 1% /dev/shm none 1014140 124 1014016 1% /var/run none 1014140 0 1014140 0% /var/lock none 1014140 0 1014140 0% /lib/init/rw /dev/sdd1 39497 4916 34582 13% /media/boot /dev/sdd2 1857948 93928 1669640 6% /media/rootfs
Set the correct options installer
The option (/dev/sdd) SD device could vary , and its depends on each PC and SD card. The option (/dev/ttyUSB0) Serial port for target communication allow the pc to have a console running on the target. The options Create and format the SD partitions (FAT and Ext3) , allow the SDK format the SD card and create two partitions A FAT partition: I'll have the bootloader , xloader and kernel images
A linux partition (Ext3) to [*] Create and format the SD partitions (FAT and Ext3) Bootloader destination (Flash) ---> Kernel destination (SD) ---> File System destination (SD) --->
There are three files required on the first (FAT) partition to boot your Overo:
MLO:
the boot-loader loader - this small program is loaded into the OMAP3 processor's static RAM. It does some minimal configuration of system memory and io pins and then loads the second file.
u-boot.bin
the boot loader image
At a minimum an embedded bootloader provides the following features:
- Initializing the hardware, especially the memory controller.
- Providing boot parameters for the Linux kernel.
- Starting the Linux kernel
uImage:
The linux kernel
You can build these yourself and download pre-built images. or use the SDK installer. It is important that these three files have precisely these names. , but the SDK installer automatically set those names.
Running the SDK installer
The SD card must be on on the SD Card Reader Be sure u-boot is running on port /dev/ttyUSB0 and none process (like minicom) is using it
on the terminal run the following command
make install
The SDK installer will automatically set all the environment on the u-boot and save the images to the SD Card