Frequently Asked Questions - WxDuck
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Stand-alone WxDux
The WxDux is a matchbox-sized device that plugs into the serial port of a server or other PC which contains a variety of environmental sensors. The WxDux is powered from the serial port, eliminating the need for an external power supply.
The sensors were picked based on accuracy and a history of use in industrial sensing applications. The temperature sensor, for example, is accurate to within 0.5 degrees celsius. See the specifications sheet for all the sensor accuracies.
An internal microcontroller handles all communications with the external sensors, relieving the PC of any complex data-conversion processes. When the PC wants to know temperature, for example, it merely sends a "T" to the COM serial port and an ASCII text string containing the temperature reading is returned. Loading of the PC is minimized.
How is a web page created with the WxDux?
The supplied software creates Java server pages which are normally accessed through Port 8080. Each time you access
the web page, the JSP program queries the WxDux for the latest data and builds the HTML code you see in a web
browser.
What kind of a load does the WxDux software place on my PC?
The supplied software uses 30 megabytes of memory and runs as an NT service. We test on a 700MHz PC and when
a web page request comes in, CPU usage shows about 2%. Every 60 seconds the software writes to an Excel file
and that briefly shows approx. 2% CPU usage as well.
Why did my Duck just start to use a huge chunk of processor time, and why can't I access the web page any more?
There is a memory-leak bug in the Java code which runs the duck, which requires it to be
restarted once every 24 hours to avoid this problem. The software should have installed a
helper task that would take care of this, but you can set it up to be a automated task in windows.
This is, unfortunately, a bug in the Java runtime environment itself, and beyond our control.
Why doesn't the WxDux need a power supply?
It uses two of the serial data lines (DTR and CTS) from the PC as power. The software
supplied turns these lines on. Each line can supply 5 VDC @ 5 mA; together, they supply
enough power to run the WxDux.
How far can the Web Cam be from the PC using the WxDux?
16 feet is the USB spec. You can go further using a USB hub.
Can I rename the IO sensors on a Duck like I can a goose?
No.
We have a Duck, how can recover our password on the duck?
If you forgot your duck password you will need to uninstall and reinstall the duck software.
