> USB is good technology and it only needs a few little > improvements in future revisions to specifications. And, if > vendors always support backward compatibility on USB then we > are in fat-city.
USB is another example of technology ignoring marginal applications. 1) There is, to my knowledge, no currently available USB chipset that supports standard data rates below 300 bps (thus no baudot). 2) USB chipsets and the USB bus itself operate at much higher clock and data rates than the UART/serial ports they replace with results in a much larger problem with radiated RFI. 3) Typical USB cables are much more "cheaply made" than a quality RS-232 cable and are more prone to failure. The failure often appears as an open shield with greatly increased noise. 4) USB port "power management" is often unreliable, particularly if the USB device is used with a DLL driver instead of an "USB Converter" driver. This results in the spontaneous, random "loss" of connectivity. 5) all devices connected to a single USB "root hub" operate in a polled, time shared basis. The time slotting makes accurate real time events (e.g., bit flipped CW) even more difficult. With its plug and play features, USB is very handy for consumer toys and games but it is severely lacking in many other ways. 73, ... Joe, W4TV > -----Original Message----- > From: elecraft-boun...@mailman.qth.net > [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Phil Hystad > Sent: Sunday, November 22, 2009 11:54 AM > To: Elecraft > Subject: Re: [Elecraft] KUSB Adapter Alternative > > > "...never a USB problem again!" > > Actually, I don't think there are USB problems. USB is a > very good standard that supports a large variety of devices > and configurations. The specification allows for simple > point-to-point interface as well as hub/hosting, device > sharing, and a number of other useful things. > > However, there is a problem in how interfaces to a computer > have evolved and the problem seems to always be associated > with dealing with old antiquated technology while being faced > with new standards and new capability. For example, when PCs > were first introduced, the parallel port seemed to be the > ubiquitous interface medium. If you have some custom device > that needed to talk to the computer, the parallel port was > the way to go since it was incredibly simple -- merely > asserting voltages on different lines for the most part. > > Next, the serial port became popular because the UART > technology started becoming a commodity and available to a > lot of different hardware vendors. > > But, the parallel port held on long after the serial port > showed superior (in many ways) connectivity. There was a > time not long ago when there was a parallel and serial port > discussions not unlike this KUSB discussion. > > In my opinion, since the serial port became so popular that > it stayed around much longer then it should have. Computer > vendors would have probably done justice to this movement by > removing support of the serial port much earlier then now is > happening. I see it as a good thing that now a serial port > is often only offered as an option on some computers and not > available at all on others. > > USB is good technology and it only needs a few little > improvements in future revisions to specifications. And, if > vendors always support backward compatibility on USB then we > are in fat-city. > > OK, off my soap box. > phil, K7PEH > > > On Nov 22, 2009, at 7:28 AM, k7hbg @dslextreme.com wrote: > > > Hi Everybody; > > As the KUSB discussion thread continues on, I'd like to suggest an > > alternative. All motherboards, except 40 year old ones, > sport a PCIE > > port or two. There exists a whole > > bunch of converter cards that ride the PCIe bus and convert > to serial ports, > > parallel ports, printer ports > > and most any other data transfer protocol. > > A good example of this can be found at Tigerdirect.com. A > PCIe bus to > > printer port with two com ports adapter > > card for $39.95. What a deal! And never a USB problem again! > > 73's Bob, K7HBG > > ______________________________________________________________ > > Elecraft mailing list > > Home: http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/mmfaq.htm > > Post: mailto:Elecraft@mailman.qth.net > > > > This list hosted by: http://www.qsl.net > > Please help support this email list: http://www.qsl.net/donate.html > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
