Rob Kenney

I have just come into a 1994 WRX sti,  I opened the ecu  case and found the link computer it reads on the back LINK 1996 SUBARU V3.3. On the front a sticker on chip reads WRXROAD 421  and another stocker reads 585 Could anyone please help me Identify this computer and what functions it has, also is it PClink tunable ? Is it possible to upgrade the firmware ?  Kind Regards Rob