Subject: Re: [libftdi 0.18] SPI with CBUS Bit-banging FT232H
>>>>> "Alex" == Alex Stefan <alexandru.stefan@xxxxxxxxxxx> writes:
Alex> On 7/4/2011 7:54 PM, Uwe Bonnes wrote:
Alex> I should have been more specific. I was refering to ideas on how I
Alex> can improve the USB timing.
Queue as much as possible in one request. Read as large as possible chunks.
Be sure the FT232H gets recognized as a USB-2.0 device on your PC. If you PC
setup isn't right and the device is only connected to a " Linux Foundation
1.1 root hub" as seen with lsusb, only 1 mS frames will be used as opposed
125 us microframes on a 2.0 hub.
B.t.w. with the older FT2232D devices, it helped to connect a USB-2.0
external hub between the device and the root hub. The hub was forcing Linux
to use microframe to the USB-2.0 full-speed FT2232D, while directly
connected only normal 1 ms frames were used.
Uwe Bonnes bon@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Institut fuer Kernphysik Schlossgartenstrasse 9 64289 Darmstadt
--------- Tel. 06151 162516 -------- Fax. 06151 164321 ----------
libftdi - see http://www.intra2net.com/en/developer/libftdi for details.
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