This Embedded Controller (EC) consists of a 8051 micro-controller, a dedicated LPC interface to communicate with the processor, and an SPI Flash ROM interface. The SPI Flash ROM supports two code segments, and a table of Manufacturing Data. The EC supports the Boot Hub Protocol, allowing the XO's main processor to boot from one of the code segments in the SPI Flash.
The EC, implemented as a KB3700, has a paramount importance in controlling the XO when the CPU is not active. To do so, the KB3700 communicates with the CPU via the EC protocol over a physical LPC interface. For more information, see the Ec specification.
The procedure to run ec-dump over internet in a wireless connection is:
ok wifi media lab 802.11 *change it to your name AP ok fl http:\\22.214.171.124\~joel\ec-dump.fth *change to your AP IP direction
Running ec-dump over internet and saving the file in a USB key:
ok wifi media lab 802.11 *change it to your name AP ok fload http:\\126.96.36.199\~rafael\to-file.fth ok to-file u:\ec-dump fload http:\\188.8.131.52\~joel\ec-dump.fth
OpenEC firmware project
The firmware running on the XO's EC, while heavily modified and supported by OLPC, was originally written by two different companies. OLPC has had no success convincing those companies to open source their code.
The OLPC community is now working on OpenEC, an Open Source implementation of the XO's Embedded Controller firmware. It currently is in an early stage and not functional yet.