LOGICWORKS 5 SYMBOL SOFTWARE
LOGICWORKS 5 SYMBOL CODE

This will create a new empty circuit window on the screen. Select the New command in the File menu then choose the Circuit item.

We now have two steps left: first to fill in the actual behavioural part of the VHDL model, and then to build a test circuit to make sure it works. It has also created a device symbol with entries linking it to the file. The Model Wizard has now created a VHDL model file that describes all the inputs and outputs, but has no actual behaviour.

Save the COUNT8 model file in the default location, or find any suitable folder for it.

This step is necessary because the name of the file will be stored with the component. A standard Save As box will appear asking you to save the VHDL model file.

Once you have selected a library, click the Finish button.

If you do not have a work library open, use the Open Lib button to open an existing library, or the New Lib button to create a new one.

LOGICWORKS 5 SYMBOL SOFTWARE

Future upgrades to the software might replace those libraries, and you could lose your work. Note: We do not recommend saving your own components into the libraries supplied with LogicWorks. If you already have a work library open in the list, you can select it now.The last panel allows you to choose the library into which you want to save the new symbol. Once you are satisfied with the pin locations, click Next button.If desired, move the pins to different locations on the symbol by dragging and dropping names from one box to another.For the Destination selection, choose “Create a new symbol with the specified model attached.” The dialog box should appear as follows:.For the Source selection, choose “Create a new, empty model.”.Select the Model Wizard command in the VHDL menu.Select the New command in the File menu, and then double-click on the VHDL selection.First, close any open circuit diagrams or VHDL files.We’ll also take the opportunity to use vectors, or multibit signals. We’ll now look at how we can use VHDL to describe the operation of a device that is going to be used in a LogicWorks circuit diagram. This delay is due to the AFTER 1 NS specification in the VHDL model.Ĭreating a VHDL Model for a Device Symbol Note that there is a 1-ns delay between input changes and the corresponding output change. Now try changing the input values again, and watch the effect in the timing diagram.You could also have done this to the Timing tab, if desired. This command places the I/O Panel in a separate, floating window so that you can view both at the same time. If the name IOPanelDefault.html is not already displayed, click on the list and choose the item ending with IOPanelDefault.html. Check the selection list at the top of the I/O Panel.Note: If the I/O Panel has already been used, you might need to click the I/O Panel tab in the Results Panel in order to bring it to the top. This will cause a new panel to be displayed in the results area at the bottom of the screen. Now we need a method of feeding inputs into our design and checking the outputs.

You will now see the VHDL text document turn gray to indicate that it cannot be edited while the simulation is running. Click the Run ( ) button to start the simulator.Locate the line that starts - Your VHDL code, and replace it with.You should receive a warning that output OUT1 has not been assigned You will notice that a new panel appears at the bottom of the screen with the compilation results. Go to the VHDL menu and select the Compile command.Before we proceed, we must verify that this is a correct VHDL file.

LOGICWORKS 5 SYMBOL CODE

We now have a complete VHDL description of a component having the desired inputs and outputs, except that no code has been added to describe the actual behaviour of the device. –Your VHDL code defining the model goes here You should now see a new document window open containing text like this: Click the Finish button to create the model file.IMPORTANT: The settings in the Func column must appear as shown above! Enter the name OUT1, and click the Add Single Bit button.Go back to the top of the panel and change the Function selection to Output.Enter the name NEG, and click the Add Single Bit button again to add the second input.The note above about names in VHDL applies also to input and output names, so you have to be sure to use something that isn’t a reserved word. Enter the name POS for the first input.Set the function to Input, if it is not already.In this case, we wish to add two single-bit inputs and one single-bit output. We now specify the “interface” to the model, that is, what its inputs and outputs will be. For example, AND would not be a valid name. Note: Since this name will be used in the VHDL source file, you cannot use a VHDL reserved keyword or anything containing invalid characters as a name.

Enter a name for the new model, such as AND1INV.

Logicworks 5 symbol