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Subject: Minimum chunk size and latency

From: Daryl Lee <daryl@xxxxxxxxxxxx>
To: Libftdi List <libftdi@xxxxxxxxxxxxxxxxxxxxxxx>
Date: Tue, 23 Jun 2009 11:11:16 -0600
I'm doing my first libftdi app, and I don't quite understand "chunk size"
and latency.  I'm sending 32-byte messages to my device and getting 32-byte
messages back.  I need to do this at 1 millisecond intervals.  I find
experimentally that setting chunk size to 32 doesn't work very well.
Setting it to 64 works better, but the time to write the message out is
usually too long.  This is a port from Windows software using FTDI's own
drivers, so there's a lot of new stuff for me to figure out.  I'm going to
give async a try, but I wonder if there is some good explanation of latency
and chunk sizing somewhere?

-- 
Daryl Lee
www.daryllee.com

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