Hi Phil,

As I told you before I will buy a QS1R and adapt Linrad to it if I
can find understandable code. Now you say that libqsio is plain C
and that you told me that before.

This is what you wrote Dec 31 last year:
> Again, there is ONLY ONE version of the firmware and you can see an
> example of how to talk to the QS1R firmware by this code:
> <http://code.google.com/p/qssdrcode/source/browse/trunk/qs-library/libqsio-win32/qs_device.cpp>.
> There are both libusb and WinUSB examples in SVN.

I had a look at it then and could not understand any of it.
Now I have looked at it again and I find things like this.

QsDevice::~QsDevice()
{
        if (h_wusb)
                WinUsb_Free(h_wusb);
}

QsDevice is declared class in the header and I have never seen
something like that in a C program. My C reference book has
no information. 

The official site: <http://www.srl-llc.com> has a link to
QS1R SVN which leads to |http://code.google.com/p/qssdrcode>

On that page I read: You do not have to have a Google account 
for ready-only access, just use the following address:

<http://qssdrcode.googlecode.com/svn/> 

This link is broken.
"The requested URL /svn/> was not found on this server."

I am sorry, but I do not have the skils needed to write code
for the QS1R on basis of the information I currently have.

73

Leif

 
> --- In [email protected], Leif Asbrink <l...@...> wrote:
> 
> > I have made measurements on the QS1R. The hardware is very good.
> > The firmware version in the unit I tested was mediocre with 
> > very low suppression of aliasing spurs. In your application
> > it would not matter at all since your front end would filter
> > out the aliasing signals that are many MHz away from the
> > desired frequency. 
> 
> You wrote in an email to me that you found two large alias responses at the 
> sampling rates of 1.953125 MSPS and 62.5 kSPS.  This was with the FPGA file 
> that supports operation of the QS1R with Winrad, not SDRMAXII.  The other 
> sample rates supported in Winrad is 2.5 MSPS, 1.56250 MSPS, 1.25 MSPS, 625 
> kSPS, 312.5 kSPS, 250 kSPS, 156.25 kSPS, 125 kSPS, and 50 kSPS all in the 
> same FPGA file.  The initial release of the FPGA file for Winrad included all 
> of those sample rates to be able to test the highest rate that any given PC 
> would be able to keep up with in Winrad.  Unfortunately the 1.953125 MSPS and 
> 62.5 kSPS rates were compromises because of how the filtering is implemented 
> in one single FPGA file to support all those rates.  Normally I would just 
> drop those two offending rates from the list because they would not normally 
> be used, for example, to record the whole AM broadcast band you would select 
> the 2.5 MSPS rate or the 1.5625 MSPS rate or the 1.25 MSPS rate which would
  g
>  ive you 2.0 MHz and 1.25 MHz and 1 MHz bandwidths respectively.  If someone 
> needs a rate of 1.952135 MSPS a FPGA DDC file can be created that has very 
> good alias suppression at only that rate.  Those two offending rates were a 
> side effect of including all those rates in a single FPGA file instead of 
> creating a file for each sample rate (which is then possible to pick filters 
> that give overkill on alias suppression among other parameters). It is a 
> similar situation to certain configurations of the AD6620 DDC in the SDR-IQ 
> and SDR-14 - some selections of filters produce very poor alias suppression 
> and you just avoid setting those filter parameters. I believe Perseus 
> generally uses individual FPGA files for each sample rate supported. It has 
> nothing to do with firmware - it is completely controlled by the filters in 
> the particular FPGA DDC file that is loaded.
> 
> > I have failed to get the information about
> > how to include support for the QS1R in Linrad. It is said to
> > be open source so I assume it is doable, but I have not 
> > found any API specification that could meke it reasonably
> > easy for me. 
> 
> I know that you have said that you don't do C++ (which is what QS1RServer and 
> SDRMAXIV are written in).  I have tried to point you in past correspondence 
> to the libqsio shared library written in pure C which is the best example of 
> how to communicate with the QS1R.  The open source code for this library has 
> been available from the beginning in the QS1R SVN which anyone can download 
> and use.  In fact, many people have done so and are now interfacing to the 
> QS1R hardware in specialized applications with MATLAB, LABVIEW, and GNURadio 
> to name a few.  With the library you have no better documentation on how to 
> interface with the QS1R than the actual C source code which can be used 
> directly or as an example of "HOW TO".
> 
> Phil N8VB
> 
> 
> 
> 
> 
> ------------------------------------
> 
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