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I have just replaced the Winrad V1.33 + WinUSB-based DLL on my
weaksignals Web site :<br>
<a class="moz-txt-link-freetext" href="http://www.weaksignals.com">http://www.weaksignals.com</a><br>
<br>
Now there are two DLLs :<br>
A normal one, which should be used in almost all the cases, named
ExtIO_HPSDR.dll<br>
and a low CPU consumption one, named ExtIO_HPSDR_LowCPU.dll, which is
meant for really slow PCs, let's say a monocore at 1 GHz.<br>
<br>
The difference between them is the block size used for the
communication between the kernel portion of the driver and the ring 3
(user)<br>
part. Making that blocksize small has the beneficial effect of a really
low latency, especially when the playback is done through the<br>
Mercury DAC, but at the price of an increased CPU time, in particular
the kernel CPU time.<br>
<br>
The LowCPU DLL uses a greater blocksize for a reduced CPU load (less
transitions between ring 0 and ring 3), but of course the latency is
greater...<br>
Start with the normal DLL, and check the CPU load indicator of Winrad.
It it becomes too often red, then use the other one.<br>
<br>
And remember when installing the WinUSB driver, to follow the advice in
my previous message, i.e.<br>
<br>
- After the install, switch off the HPSDR hardware<br>
- Reboot the PC<br>
- Switch on HPSDR again<br>
<br>
I am now editing my source code adding the relevant copyright notice
(thanks Bill), and will upload to the SVN repository the source code of<br>
the DLL, which contains in it, in a separate module, the WinUSB code. I
have also rewritten the utilities for loading the microcode into the FX2<br>
and the firmware into the Mercury FPGA. They are not anymore separate
utilities, it is all done seamlessly inside the initialization code of
the<br>
WinUSB.<br>
<br>
Feedbacks are obviously welcome<br>
<br>
73 Alberto i2PHD<br>
<br>
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