Hi Peter To use the processor most efficiently, programmers can separate pieces of their code into 'threads' which are like mini-programs in that they have their own processing loops, variables, etc. You can see it, for instance, in most programs when you print something and you can still do things in the program (the master program has created a thread to generate the printed report and spool it to the print spooler). This allows us, for instance, to allow you to use the programs graphical interface while we are receiving traffic from the internet, digital streams from you radio, etc. If we didn't have threads, you would not be able to do anything while we were checking for data from the internet, etc.
This is a simple explanation so I am sure other programmers will see inaccuracies in the exact description but its a general view. So, in powerSDR you have different threads that are sending info to the radio versus receiving info from the radio. Ever wonder how the radio can continue to receive signals while its transmitting? Threads! So when you require the high bandwidth capability of the sum of traffic via all of the threads talking over the firewire bus, with the latency requirements we all have (none if you pleas!) then it gets a bit congested over a plain USB2 connection. SDR devices that use USB2 are not running three separate receivers and a transmitter at the same time (although there are some really smart guys out there so they for sure can always come up with some solution to bypass some of the limitations). The fact that the new 1500 can use usb tells me that it will not allow SDR speeds greater than 48K, some restrictions on the size of buffers allowed and doesn't have a second receiver in there. Hope that helped! Neal Campbell Abroham Neal Software www.abrohamnealsoftware.com (540) 645 5394 NEW PHONE NUMBER Amateur Radio: K3NC Blog: http://www.abrohamnealsoftware.com/blog/ DXBase bug reports: email to [email protected] Abroham Neal forums: http:/www.abrohamnealsoftware.com/community/ On Mon, Jan 11, 2010 at 11:50 AM, Peter G. Viscarola <[email protected]>wrote: > > > > USB can not handle the number of threads at once. > > > > I really don't want to beat this "why use 1394" horse any deader than we've > beat it in the past few years, and I'm not trying to argue. But I can't > relate "USB" and "number of threads"... can you say more about this? > > Note that he's talking about USB 3.0 (Superspeed), which has a speed of > 4.8Gbps. > > Peter > K1PGV > > > _______________________________________________ > Flexedge mailing list > [email protected] > http://mail.flex-radio.biz/mailman/listinfo/flexedge_flex-radio.biz > This is the FlexRadio Systems e-mail Reflector called FlexEdge. It is used > for posting topics related to SDR software development and experimentalist > who are using alpha and beta versions of the software. > _______________________________________________ Flexedge mailing list [email protected] http://mail.flex-radio.biz/mailman/listinfo/flexedge_flex-radio.biz This is the FlexRadio Systems e-mail Reflector called FlexEdge. It is used for posting topics related to SDR software development and experimentalist who are using alpha and beta versions of the software.
