[hpsdr] about latency growth with HPSDR

[Willi Reppel]

Hi Phil and Riho,
Yes, Kiss seems to be better in handling the data stream over Ethernet compared to the different PowerSDR programs. With Ozy I experienced audio dropouts which are gone after installing Metis. Now the skin of PowerSDR  freezes temporarily and it takes several seconds before it starts moving again, about the same time the PC needs to find Metis on startup. This never happens when using the Kiss console and said freezing may also relate to Phil´s numbering of the data frames, sent in both directions. I tried all possible settings in PowerSDR but could not find one that prevents occasional freezing. Using Kiss, I can set the process priority in Windows Task Manager to "low" and no freezing occurs. Hope my observations help to improve HPSDR-programs. 
vy 73 es gl de
SM6OMH  Willi
MS XP 32. AMD Sempron 3400+, 1,81 GHz
Atlas
Metis v1.0 (installed recently)
Mercury v2.9
Penny v1.2 
Kiss v1.0.4  Recent KD5TFD & W5WC PowerSDR programs.  
  ----- Original Message ----- 
  From: Riho B., ES7AAZ 
  Cc: hpsdr at lists.openhpsdr.org 
  Sent: Saturday, October 01, 2011 12:24 PM
  Subject: Re: [hpsdr] about latency growth with HPSDR


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




------------------------------------------------------------------------------


  Thanks Phil,

  As I see I need to upgrade my hardware. I'm still Ozy user since most
  of the time I'm running my HPSDR @ 48 kHz, there's no need for
  higher sampling rates for me.


  Thanks again !

  73's
  Riho, ES7AAZ.


  1.10.2011 10:14, Phil Harman kirjutas: 
    Hi Riho,

    You may care to do some tests on you system using KISS Konsole since I suspect you are dropping packets between the PC and HPSDR hardware.  If you are only losing the odd packet then you are not going to hear them.

    The Metis Ethernet code has a packet number included in each data frame both to and from the PC. KK will indicate if a  packet is lost and what the expected and received  packet numbers are.  Similarly Metis will light a LED if it misses a packet.

    Using KK with Metis at 192ksps I have never seen a missed packet in either direction - in fact I had to deliberately send incorrect packet numbers to check the code was working!

    I'm also currently doing some work that involves time stamping the data from Mercury via Metis - again no dropped packets. 

    The PC has absolutely no idea what the sample rate is of the data it is being sent. It's not acceptable that an SDR can't be used for DRM, SSTV etc - this needs to be investigated and corrected.

    73 Phil...VK6APH 




------------------------------------------------------------------------------


  _______________________________________________
  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/

--
I am using the free version of SPAMfighter.
We are a community of 7 million users fighting spam.
SPAMfighter has removed 1037 of my spam emails to date.
Get the free SPAMfighter here: http://www.spamfighter.com/len

The Professional version does not have this message
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openhpsdr.org/pipermail/hpsdr-openhpsdr.org/attachments/20111001/978e1380/attachment-0004.htm>