What is the SoC on the ARM9 board TS-7800?
The Technologic Systems website you linked-to says here that :-


  The TS-7800 is a RoHS compliant Single Board Computer (SBC) based on a Marvell MV88F5182 500MHz ARM9 CPU


Although this processor doesn't seem to be mentioned on Marvell's website (obsolete, perhaps?), Technologic have a PDF manual here (dated 2008) which described the device as a "Feroceon Storage Networking SoC".

The manual isn't a "newbie" guide for non electronic engineers, but as a software developer, you should find it a useful resource.