I found a datasheet for the TF-331 on the kynix site:
Datasheet:
https://www.kynix.com/Detail/839420/TF-331-ACL.htmlOverview: pdf.dzsc.com/88888/200813104039864.pdf
This is a 8051/80390 core device designed by what appears to be a now-defunct taiwanese company called Taifatech. This is a nice SoC solution if you want a h/w accelerated network solution. It supports external flash memory, 10/100 Mbs ethernet, external Flash memory. all you have to add is PHY inteface chip (such as Davicom DM9161A).
It was supported by older Keil compilers (Keil C v7.10, circa 2007).
I started searching for this as I was trying to repair an Aviosys IP9258 (PDU) with a faulty ethernet interface. They had erased the chip identifier from the main components, it took a while but finally I identified them all. The old models commonly used this in conjunction with the Davicom DM9161A as the ethernet transceiver. The ethernet interface doesn't use any magnetics, so is prone to damage if have any over voltage on the line.
If anyone has any further info on programming this let me know.
Joe