[Elecraft] K3 - Windows Blue Screen with USB to Serial Adapters during firmware loads. New Device Driver required.

[Dick Dievendorff]

Elecraft has received a number of reports of very slow firmware load,
sometimes accompanied by a Windows "blue screen", when using some USB to
Serial Adapters when loading the DSP with the most recent versions of the K3
Utility.

Many USB to Serial Adapters, including the Elecraft KUSB, contain a Prolific
Technologies Chip Set, and some of the earlier Prolific device drivers
(including the one on the CD shipped with the KUSB) suffer exceptions during
error recovery situations.  The result is a Windows "Blue Screen".

If you have this sort of USB to Serial adapter, the remedy for the class of
errors we've seen is to install an updated Prolific USB to Serial Adapter
device driver.  

To determine what driver you have installed now, on Windows 2000, 2003, XP
and Vista:

1)	Plug the USB to Serial Adapter into a USB port on your computer.  It
doesn't need to be connected to the K3 for this test.
2)	Right click the "Computer" or "My Computer" and select "Manage".
3)	In the left pane of "Computer Management", select "Device Manager".
4)	In the right pane tree view, click the + sign next to Ports (COM and
LPT).
5)	Look for a COM port that says something like "Prolific USB-to-Serial
Comm Port (COM4)"
6)	Double click that entry to open a Properties viewer, and select the
"Driver" tab.
7)	The driver manufacturer (Prolific) and driver version should be
visible on the Driver tab.

If you are using Windows Vista, the appropriate device driver is the one you
get from Windows Update when you first plug in the USB to Serial Adapter.
I have version 2.0.2.1, and it works fine with the K3 Utility. 

If you are using Windows XP, Windows 2000, or Windows 2003, the currently
available device driver is version 2.0.2.8, and it's available from the
Prolific web site, http://www.prolific.com.tw/eng/downloads.asp?ID=31.  This
driver may also work on Vista, but I haven't done that as I'm getting
working drivers from the Microsoft Update facility.

Prolific Driver version 2.0.2.4 also works fine with the K3 Utility.

If you're using the driver that came on the CD with the KUSB, this is an
update you really want to make.  We've had at least a half-dozen reports of
this sort of failure, and all were corrected by installing the current
device driver from the Prolific site.

The K3 Utility issues standard Windows 32 API serial port requests.  However
sometimes in error recovery situations a pending asynchronous Read operation
must be cancelled (we waited a while, and it didn't complete in time), and
cancelling pending I/O has on occasion been an area of difficulty for some
device drivers.   It's hard to test.  Prolific has it right now.

The link to the Prolific web site is in the Troubleshooting section of the
K3 Utility Help, and Eric has recently added a link to the Prolific
Technologies driver update web page on the Elecraft K3 Software page at
http://www.elecraft.com/K3/k3_software.htm.

The chipset in the KUSB is a Prolific Technologies 2303, and the top link on
the page is the appropriate driver. Version 2.0.2.8, the file is named 

wd_pl2303_v20019v2028.zip

Dick, K6KR