[hpsdr] 16-bit DUC/DDC transceiver ODYSSEY

[George Byrkit]

If you are only receiving, it possibly doesn't matter, as long as you receive all packets.
If you are trying to receive in 'close-to-real-time' AND transmit, such stack latencies do
matter!  The issue is that all operating systems include efficient drivers for Ethernet.
Not so much for USB or USB3.  We use LibUSB0 for our driver, we tried WinUSB, which had
much worse stack latency, and abandoned it, while looking for signed 64 bit USB drivers
that we could use.

USB is likely OK for HackRF for example.  But it isn't trying to be an HF radio, really
(apologies if necessary to Michael Ossman.)

George

-----Original Message-----
From: Hpsdr [mailto:hpsdr-bounces at lists.openhpsdr.org] On Behalf Of John Ackermann N8UR
Sent: Thursday, January 28, 2016 5:51 PM
To: hpsdr at lists.openhpsdr.org
Subject: Re: [hpsdr] 16-bit DUC/DDC transceiver ODYSSEY

***** High Performance Software Defined Radio Discussion List *****

Although, the new Ettus devices use USB3 for pretty high bandwidth.  The 
problem apparently is that there are still a lot of USB3 host chips that 
don't implement the spec very well.

On 1/28/2016 5:18 PM, George Byrkit wrote:
> ***** High Performance Software Defined Radio Discussion List *****
>
> And USB has horrible stack delays compared to Ethernet.  That's why we have gone away
from
> USB (Ozy, Magister) to Ethernet (Metis, Hermes, Angelia, Orion).  Those who have not
> learned the lessons of history are doomed to repeat them...
>
> 73,
> George K9TRV
>
> -----Original Message-----
> From: Hpsdr [mailto:hpsdr-bounces at lists.openhpsdr.org] On Behalf Of Helmut
> Sent: Thursday, January 28, 2016 4:59 PM
> To: 'Serge Smirnoff R6YY'; hpsdr at lists.openhpsdr.org
> Subject: Re: [hpsdr] 16-bit DUC/DDC transceiver ODYSSEY
>
> ***** High Performance Software Defined Radio Discussion List *****
>
>
> _______________________________________________
> HPSDR Discussion List
> To post msg: hpsdr at openhpsdr.org
> Subscription help: http://lists.openhpsdr.org/listinfo.cgi/hpsdr-openhpsdr.org
> HPSDR web page: http://openhpsdr.org
> Archives: http://lists.openhpsdr.org/pipermail/hpsdr-openhpsdr.org/
>
_______________________________________________
HPSDR Discussion List
To post msg: hpsdr at openhpsdr.org
Subscription help: http://lists.openhpsdr.org/listinfo.cgi/hpsdr-openhpsdr.org
HPSDR web page: http://openhpsdr.org
Archives: http://lists.openhpsdr.org/pipermail/hpsdr-openhpsdr.org/