[linux-dvb] Slow control data from dvb-usb (VP7045)

Patrick Boettcher patrick.boettcher at desy.de
Mon Nov 28 09:15:13 CET 2005

Hi Jeremy,

On Mon, 28 Nov 2005, Jeremy Nysen wrote:
> The control data requests for dvb-usb devices (I'm testing with a VP7045 
> device) is quite slow. Each request can take a few hundred milliseconds to 
> complete and return data. This gets longer when multiple data bytes are 
> requested from the frontend. eg. generating 3 requests for 3 register bytes 
> of AGC information for the MT352 in the device can take a whole second. If I 
> perform 6 requests it takes twice as long.

Reading the MT352 is an extension, which is (afair) not done in the 
Windowsdriver made by Twinhan. Additionally I have a large msleep in every 
read-function, because reads are failing "all the time". You can try to 
reduce the read-delay in vp7045.c to an optimal value.

best regards,

   Mail: patrick.boettcher at desy.de
   WWW:  http://www.wi-bw.tfh-wildau.de/~pboettch/

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