Re: Cypress FX2 device driver & loopback speed

You need to transfer larger buffers. Usually, separate single-packet
requests cannot be scheduled into the same microframe. Large requests can
execute many packets per microframe.

"David" <know_devig@xxxxxxxxxxx> wrote in message
news:1142222714.635068.28730@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Hi ,
I am using Cypress FX2 USB controller in out High speed USB device.
I am performing bulk loop-back operation (same as per sample from
Cypress)
I am transfering total data for 1 MB using 512 bytes at a time. That
gives ~1955 packets.
I observed that ~ 150 times ReadFile or WriteFile from application
takes 16 millisecond to complete transfer of 512 bytes, which seems
long to me.

this 16 millisecond response costs my overall speed to go down as low
as 10 Mbits/second or so. I want to achieve atleast 90 to 110 Mbits per

second speed.


Is this because of bulk transfer? Can this be fixed? or I need to
fine tune things somewhere?


Thanks,
David



.

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