Fast transfer feature of the EZ-USB AN2135SC - FRD#, FWR# lines not toggling

Question: The FRD# and FWR# lines are not toggling on the AN2135SC if the absolute address is 0xF000 or 0x8051 (outside the on-chip RAM space). The PORTACFG bits, FRD# and FWR# line signals, and data lines D0-D7 are correctly set.Is this a documentation problem or does the FRD# and FWR# lines not work on devices without the external address bus?

 

Answer:

The fast transfer mechanism provides access to on-chip memory space only.