Honored Contributor
Honored ContributorThats funny, I'm also multiplexing 24-bit words into the 8-bit USB bus :)
Anyway, thanks for the FTDI-document - seems like they relaxed the 11 ns setup times to 8 ns. This will surely give me some nice slack. I can't take the easy route like you did with ignoring TXE since I have huge data-buffers to send continously more or less. Though, this morning I managed to get timing closure and good function of my interface even with the 11 ns timing. The resulting speed (writing from Cyclone-3 to FTDI2232H and reading from a Linux PC up to a user-mode program using libusb) was a whopping 43 mbyte/s! Satisfying! And it seems it works without glitches (yet). As a side-effect I learned a lot of SDC as well :)
