Screenshot for April 19, 2001 (Latest Update) This
is how a workbench would look like, minus the boards. |
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Welcome
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Team D is creating a Remote
Laboratory Station that virtually simulates Electrical Engineering laboratory
equipment for the purpose of distance education. Our product will directly
increase enrollment in Northern Arizona University engineering courses by
allowing distance-learning students to take engineering lab courses. This
increase in enrollment will thereby increase university income and university
prestige.
Update
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of now our project is progressing to the point of testing combined components. Our
USB interface controller is being shipped, and should arrive in a day or two.
Our FIFO's will be ordered once we determine the speed of the USB
controller as it interfaces with LabVIEW. As
long as our USB controller works as advertised our FIFO depths and speeds should
stay the same as shown on the block diagram. We
have downloaded the DLL (driver files) and LabVIEW drivers for this USB
controller and have set up a folder on our computer at our workstation that
contains all LabVIEW VI's to date. Some
of the test VI's that were created over the Christmas break were a "test_Oscilloscope"
VI that will be used for initial USB interfacing, "Data_Capture" VI
that is used to experiment with capture speeds, and a "Boolean_Reader/Grapher"
VI that shows how to create and graph a Boolean array. We
have drawn up a preliminary block diagram that contains all components and the
overall flow of the circuits (these block
diagrams are attached). We
have also determined speeds and resolution sizes for our A to D's and D to A's,
as well as our low pass filter for wave capture.
We will be ordering these parts within the week; once again, after the
USB interface is tested and its peak speed determined.
Calculated
Results:
After
preliminary testing of LabVIEW it was determined that LabVIEW is extremely
slow when it comes to creating an ordered array of some large size. Because
of this we are going to be using three clocks to run the CLKIN and CLKOUT of the
two FIFO's. There are three main reasons for this:
1.
We can keep the FIFO depth down and therefore it is cheaper and we can
clock in all data much quicker.
2.
We can attain a better range of frequency (200khz, 20hz)
3.
We can maintain a better wave resolution over the most popular spectrum
of frequencies.
The
actual clock speed will be chosen by the user using a three-pole VI switch (High
(200khz to 500hz), Med (500hz to 100hz), and Low (100hz to 20hz)). These
frequencies were determined to give the High clock 2.5-1000 samples/period, and
the Med and Low clocks limits of 200-1000 samples/period.
The Med and Low upper limits were set at 200 to allow for greater
resolution at these most common frequency ranges.
Problems:
As stated before, we will not have any hard specifications on speed of wave
acquisition, or production until we test all components together, especially our
USB controller. This is due to the
large number of unknown variables when dealing with this relatively new USB
technology. As it stands now our
best guess of frequency range is 200khz to 20hz.
A
major problem we have had in the last month is getting our USB controller
delivered. It seams our order was misplaced the first time and therefore had to
be reordered. Because of this we
have been on hold for at least the last three weeks.
A
potential problem is that we may have trouble interfacing two of these
ActiveWire USB Controllers at the same time with LabVIEW.
Kevin Sova has talked to ActiveWire's technical help, and they don't
think it should be a problem. The team
will determine this by trial and error. Note:
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