adding 3rd USB device controller port to LPC54608

[belmontbob59]

I would like to add a 3rd USB device controller port to my MCU. I looked for parts and ended up with two solutions:

a) use FT120 which interfaces to MCU via parallel bus (http://www.ftdichip.com/Support/Documents/DataSheets/ICs/DS_FT120.pdf)

b)Use MAX4320E. This is SPI to USB  (https://www.maximintegrated.com/en/products/interface/controllers-expanders/MAX3420E.html)

is option(a) doable ? This means configuring the EMC to interface with FT120. I am worried about not getting EMC configured right. Option (b) looks simpler but I am worried about achieving lower USB bandwidth than If I was going with option (a) 

[soledad · Accepted solution]

Hello Bob,

At the end, it is going to be your solution,  I do not see any problem to implement your Option A),  since EMC interface it is fast enough to get the data from a USB port, 

Hope this helps.

[belmontbob59]

After doing some research on option A (FT120), I am confused on how to interface with the EMC.

FT120 has RD_n (Read Enable pin , active low) and WR_n (Write Enable pin, active low). However the EMC only provides us with EMC_WE .  WR_n will connect to EMC_WE but Where do I connect RD_n to ?