General Tips for Labs

Here a few things that will help for the rest of the semester when working on your designs.

• The most important thing for all labs and the project is to save your schematics often. Save your work in your home directory AND on a 3.5" floppy disk, since the network can go down unexpectedly taking your files with it.
  
  
• In ViewDraw, always save your schematics using "Save and Check" instead of "Save". This will tell you if there are any errors in your schematic. It will also ensure that your most up to date schematic is being converted to format needed for the other programs in Workview office.
  
  
• Always test your individual schematics and overall design in ViewSim before trying to compile to hardware.
  
  
• Some of the labs will require you to use a TA created I/O schematic. Save the provided schematic as the last page of your overall schematic.
  
  
• Always check the Reports in Xilinx Design Manager after compiling a design to see if there are any suspicious warnings such as "multiple driver" or "no driver."
  
  
• The bug with waveforms disappearing is due to doing a "full-zoom" - simple solution is to just zoom in and zoom out with F7 and F8 (or these choices on the menu bar). I haven't noticed any such problem occur when zooming with F7 and F8.
  
  
• The solid red on waveforms indicates that the value is undefined. (Solid white/light blue sometimes appears ... that seems to be fixed by a zoom in ...)
  
  
• If you close the wave display then you cannot rerun it from ViewSim without starting ViewSim again.
  
  
• You can set a input/output pin undefined by 'x ' ... this doesn't however allow it to be asserted by the logic.
  
  
• When entering a schematic into ViewDraw, make sure your components are connected to the nets (wires). Do this by selecting the symbol and dragging it around and seeing if the nets follow the symbol.
  
  
• When labeling nets in Viewdraw, just use numbers and alphabet (don't use punctuation or underscores). Also, label everying, including gates and blocks.
  
  
• Always use components from the XC4000E library unless it is a component you have designed yourself.
  
  
• When you create a symbol from your own schematic in ViewDraw, the name of the symbol must have the same name as the schematic.
  
  
• In VWave, sometimes a net that you are watching will disappear. Zoom in, Zoom out, or scroll the window, and it should return.
  
  
• VWave used to be called ViewTrace, so the TAs or the lab handouts may accidentally use ViewTrace, when VWave was intended.
  
  
• Ignore error messages about license keys and about ViewSim being out of date.