Gives instructions lengh : MCycles, TStates (please remark the 's' at end of theses words...), in [[http://www.zilog.com/docs/z80/um0080.pdf Z80 doc]] each instruction is timing described using "M Cycles" and "T States" vocabulary.
It's a "controler"(proof : you have some Set_*_To outputs), does gives orders to T80_ALU.vhdl throw T80.vhdl
Actions of this controler are :