How to stop AutoBoot on the Samsung SCS-26UC4

Written 2010-12-11

Tags:Samsung Programming U-Boot Diff password JTAG 

After downloading the Samsung source code, you may try to find differences between the stock sources, and the ones Samsung provides. This results in a list of the changes Samsung had to make to the stock sources to get their product going. After you build a serial cable for the femtocell, you also might've noticed the message 'Hit any key to stop autoboot', tried hitting a key, and the boot proceeded anyhow. Here's why.

Performing a difference between the u-boot 1.1.1 source from Samsung and the stock source from sourceforge.net, reveals a few key differences:

  1. MDOC filesystem support. This is a type of flash combined with a flash controller.
  2. OMAP1710 support(http://linux.omap.com/pub/documentation/omap_1710v1.4.txt, read the u-boot section)
  3. NFS boot timeout went from 10 seconds (stock) to 60 seconds(Samsung)
  4. These little gems in the autoboot/console code:

SamsungDiff1

SamsungDiff2

This code adds a 4-byte password of s, y, s, followed by newline or carriage return.