Re: [Ftdi-usb-sio-devel] Resetting the FTDI

[Michael P. <mic...@gm...>]

Chris Stankevitz wrote:
>> I suspect the reason for the difference in performance is due to the
>> fact that my use of ftdi_sio involves non-blocking, CPU gobbling read
>> operations from within a while loop while libftdi appears to use some
>> kind of CPU-friendly blocking read.

Again, I would suggest that you consider using a non-blocking form, and
schedule multiple read requests.  To do this, you will need to download
version 1.0, which is currently only in git:

http://developer.intra2net.com/git/?p=libftdi-1.0

The idea is that the kernel needs to have a read request already ready to go
when the time comes for the next frame.  There is a separate mailing list
for this, and there may be people with more insight there if you want to
pursue it.  Consider ftdi_read_data_submit, ftdi_transfer_data_done, etc.  I
assume you are making your assessment of which frame a packet is in using
your sniffer, rather than when your application sees it, but, when you get
to that point, there may be a few more things you need to do to make sure it
gets to you quickly.

Michael