Hi,
If you want to see S19 parsing and upload thru Ethernet, I have an example in my skeleton source code project, skeleton.zip, at the bottom of this page:
http://www.cpustick.com/downloads.htm
Basically, that skeleton will build a command-line interface for about a dozen different MCUs -- you only need to follow the MCF52233 #if's. Most of the code you care about is in flash_upgrade(), in sources/flash.c. You can enter an "upgrade" command and then paste an S19 file into a terminal emulator window connected to port 1234 of the DHCP address, and the system will upgrade its flash memory.
-- Rich
