ft245 async mode

[taha.zand]

Hi
I have a project which i need to transfer digital ADC data from fpga to PC. My fpga is spartan6-XC6SLX9 and there is a ft2232hl on my board. Chanel A is used as programmer(usb to jtag) and just port B is available to transfer data; so i decide to use it in 245 async mode. As mentioned in datasheet there is two control pins TXE and WR to transfer data from fpga to pc. I don't know how to set timing in async mode and how the TXE pin acts; does it change automatically? If yes, how mili seconds it goes high and how mili seconds goes low? can i be sure that my data transfer rate kept same as ADC rate(12Mbps) during TXE changes?
Thank you for your help.

 

[FvM]

All requested information is in the FT2232 data sheet.

--- Updated Oct 11, 2021 ---

Specifically "Figure 4.6 FT245 asynchronous FIFO Interface WRITE Signal Waveforms" and related timing values.

FT2232 incoporporated a FIFO.
Maintained data rate mainly depends on data processing on the PC side.