Attributes Overview

Attributes are arbitrary blocks of text associated with any device, signal or pin in a design, or with the design itself. Attributes have a wide variety of uses, including:

• Displaying device name, part type, value, etc. on the schematic.

• Storing data for the device model. Attributes are used to store and send data into HYPERSIM.

• Storing various HYPERSIM related data on the object (device, signal, pin or design).

• Storing any other user-defined data for various tasks of design maintenance, annotations or some other encapsulation tasks.

Attributes can be used in conjunction with the scripting and report generation features of HYPERSIM to implement powerful interfacing, customizing and error-checking features. You can define as many attribute fields as you need to store the text data required for your application.
In addition, many HYPERSIM features use attributes as temporary or permanent storage locations for data relating to a device or signal. For example, each device in a design has the name and location of the library it was read from stored in an attribute field. This allows the library to be located easily for later updating.
Attribute-based changes and programming are only for advanced users. Illegal manipulations will not be necessarily intercepted by HYPERSIM and you may corrupt device or design data and even make a design impossible to repair. A clear understanding of attributes is needed before making any changes.

Attribute Organization

Attribute Definition Table

Attributes are divided into named fields. The list of allowable field names is stored with each design in the attribute definition table. For each field, the table contains:

• the field name (up to 16 characters)

• what types of objects that field can be used in (devices, signals, pins or design)

• data entry constraints (maximum length, carriage returns, etc.)

• default settings, such as whether the field should be made visible on the diagram.

Once a field is defined in the table, its name is never typed again. When attribute data is entered for a selected object, the field name is picked from a list of allowable fields. This eliminates any chance of accidentally misspelling the field name in one object.

Primary vs. Secondary Fields

HYPERSIM has 50 or more predefined fields that are used for various program features and more can be added by the user. Most of these fields never need to be viewed or set directly by the user. To reduce clutter, attribute fields can be defined as being primary or secondary. When entering attribute data, you can choose whether you wish to see primary fields only or all fields.
The primary/secondary setting is for viewing and editing convenience only and has no effect on the meaning or internal usage of the field. This setting for individual fields can be changed at any time using the Define Attribute Fields command in the Options > Design toolbar.

Attribute Limitations

Attribute fields have the following specific limitations:

• Maximum length of field name: 16 characters

• Maximum length of field data item: 200,000,000 characters. Note: In principle, binary data could be pasted into an attribute field although this is not recommended since HYPERSIM provides no mechanism for displaying or editing this data.

• Maximum number of user-defined fields: 900

• Maximum number of displayed positions of a single attribute item: 100

Like all other circuit data, the amount of attribute data that can be associated with a design is limited by available memory.

Entering and Editing Attribute Data: Basic Procedure

To edit the attributes associated with a device, pin or signal, you can either:

• Choose the object of interest on the schematic and right-click to select the command Attributes.

• The Attributes command is also available when you select the object and use Ctrl+I.

To edit design attributes, select the Design Attributes in Options>Design toolbar.
Any of these methods will display the general attribute editing box which is used to enter or edit attribute data on a single object:

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By default the field list at the left side of this box shows only the primary fields available for the selected kind of object. You can click on the All fields button to view all available fields.

Entering Data Values

• To edit the contents of a field, select the field name in the list. The current contents of the field is displayed in the editable text box. Edit this value using the usual text editing techniques.

• Press the Done button or select another field when done. When you select another field, data entered for the previous field is saved. If the data you typed exceeded the maximum length for the field, or if it contained invalid characters for the field, then you will be asked to correct the data.

• You can view or edit as many fields as desired while in this box. No changes are made to the actual design data until you click the Done button. Clicking Cancel will abandon all changes made while in this box.

Restoring the Default Value

• Clicking the Use Default Value button sets the value for the selected field to the default value stored with the symbol. This is valid only for device and pin attributes for which a default value was

• specified. If this button is inactive (grayed out) then the value is already the default value, or no default value is present. Only devices and pins can have default values.

• See Setting Part Attributes for more information on entering default attribute values while editing a symbol.

Using the Value List Pop-up Menu

• If the selected field has an associated value list field, then a pop-up value menu will appear near the Use Default Value button. An item selected out of this menu will cause the value text box to be updated accordingly. This does not prevent the text data from being edited directly.

• When an attribute field has more than one possible value, the list is displayed in one of these menus. For example, if the sub-menu Part appears, this means there are multiple part definitions available in this device type. Selecting one of the parts in the part sub-menu causes the part attribute field to be changed for that device.

• See more information on value list fields in Using Value List Fields.

Displaying an Attribute on the Schematic

To display device, signal or pin attribute text on the schematic:

• Edit the attribute value as desired.

• Turn on the Visible switch.

When you click Done, the attribute text will now be displayed in a default position near the device, pin or signal. It can be dragged to the desired location using the pointer cursor.

• Design attributes can be displayed on the schematic using text variables. See Using Text Variables

• For information on setting the default position for an attribute on a symbol, see Using Default Position Fields.

Entering Design Attributes

To view or set attributes associated with the design itself, select the Design Attributes command in Options>Design. This command displays the standard attribute data entry box allowing you to enter attribute data for the design itself. Design attributes can be used to create variables in text blocks on the schematic and to insert global data in the Netlist output.
The Visible option is not available for design attributes, since there is no single object on the schematic to associate them with. Design attributes can be made visible by using text variables, described in Using Text Variables.

Entering Pin Attributes

You can view or set pin attributes by right-clicking on the desired pin and selecting the Attributes command.
The attribute editing box for pins is identical to the one for devices, signals and the design, except that Next and Previous buttons appear at the bottom. These can be used to view and edit other pins on the same device without having to return to the schematic and select them individually.

Attribute text right-click menu

When you right-click on a visible attribute text you have access to several editing commands. In this example the visible Name attribute is clicked:

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• The Edit command is equivalent to double-clicking on the attribute text.

• Justification is explained in Setting Visible Attribute Justification.

• Hide is explained in Hide a Visible Attribute Value.

• Duplicate is explained in Duplicate, Merge and Delete options.

• The Rotate commands allow rotating the text as explained in Rotating Attribute Text.

• The Show Field Name command is described in Showing the Field Name with an Attribute Value.

Rotating Attribute Text

To rotate an attribute text item that is already displayed on the schematic, right-click on the attribute text and select the rotation related commands starting with Rotate.

Hide a Visible Attribute Value
If you wish to hide a device, pin or signal attribute value that is displayed on the schematic (that is, remove the displayed text from the schematic, but keep the value associated with the object), you can use any of these methods:

• Right-click on the text and select the Hide command in the pop-up menu.

• Right-click on the text and select the Edit command. In the text edit box that appears, turn off the Visible switch.

• Display the general attribute editing box for the object, using the methods described earlier in this chapter. Select the field in question and turn off the Visible switch.

• Click on the Zap (delete) tool in the tool palette, or select the Zap command in the Edit menu and then click on the attribute text you wish to hide.

Any of these methods removes the displayed text from the schematic without modifying the value that is stored with the object.

If the value you are hiding is a signal name, this operation may have side effects on the connectivity represented by the signal. Hidden signal names are not controlled by the user and this operation will break the virtual connection method (see Connecting Signals by Name).

Setting Attribute Text Style

• There are two ways to set attribute text style globally for all attributes and separately for individual attributes. When an attribute has a separate setting the global command will not affect it.

• There is no way to set text style for an individual object attribute item.

• Changing the attribute text style affects all visible attributes throughout the design for all attributes that have the default setting. This may alter text alignment and position to accommodate a different text size.

The attribute text style setting affects the following types of items:

• Device and signal names.

• Bundle breakout and bundle pin labels.

• All other attributes displayed on the diagram.

but does not affect:

• Border text

• Pin numbers

The text changes are applied when the OK button in the Design Preferences box is clicked. For larger designs, there may be a substantial delay while new positions of all displayed attribute items are calculated.

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To set the global text style:

Choose the Design Preferences command in the Options> Design toolbar.
Select the Text tab and click on the Attr Text Style button. This displays the following box:

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This box allows you to select the text font, size and style used for all attributes displayed in the design.
Depending on the size of the design, there may be some delay at this point. The program must check all visible attribute items to see if there position and framing is affected by the text change.
Another method for setting text style for individual attributes is available through the definition of attribute fields (see Defining Attribute Fields).

Setting Visible Attribute Justification

• Attribute justification determines how text is aligned relative to the device it is associated with. Generally, the program chooses a justification that is appropriate for the initial placement of the text and there is no need to change it. However, if text is being modified frequently and does not reposition itself as desired, the justification can be modified individually for text items.

• To set the justification, right-click on the text item in question. In the attribute pop-up menu that appears, select the Justification command. This command allows you to change the vertical and horizontal justification used in the positioning the attribute text on the diagram. When this command is selected, the following box will be displayed:

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The selected point on the text is considered to be the reference point for the given attribute block. This point will be kept fixed if any field value or text style changes cause the box to be resized.
The Justification command affects only the position of the text relative to the associated object. It does not affect the alignment of text in multi-line text items on the schematic. HYPERSIM does not provide any method of choosing center or right justification of multi-line text items.

Displaying an Attribute Value in Multiple Locations

• You can display a single attribute value in multiple locations on a schematic. This is intended for use particularly with signals, which can be spread over large areas of a page or multiple pages. If a value is displayed more than once, editing any one of the displayed values will affect all appearances of it.

• To create multiple displayed attribute items, right-click on the text item in question. In the attribute pop-up menu that appears, select the Duplicate command. This command creates another visible occurrence of the same attribute field. This text can then be dragged or rotated to any desired position on the schematic.

Showing the Field Name with an Attribute Value

The Show Field Name command from the right-click on attribute text menu allows you to display the field name with the value on the schematic. When this item is checked, the display will be in the form fieldName=value. Selecting this command again will cause the display to revert to the normal value display. This command applies only to the selected field on the selected object.

Using Value List Fields

A value list field allows you to specify a list of possible values that can be used in a selected field. This list of values if then displayed to the user at various locations, allowing easy selection of one of the available items.
A value list field has the same name as the associated field but with .List appended. When a field named xxx.List is seen by the program, it takes these steps:

When the attribute edit box is displayed for a given object and the field xxx is selected, a pop-up menu is displayed containing all the possible values for the field. The user may then select the appropriate value from the menu.
When a pop-up menu is displayed by right-clicking on an object, a sub-menu with the field name xxx as its title appears. The list of possible field values will be displayed in the sub-menu. The user can select one of these items to directly change the value of field xxx.

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Value List Data Format

The value list field must contain a sequence of textual values following these rules:

• Items must be separated by commas. A comma is always a separator and therefore cannot be part of the value.

• The value string can contain any characters other than commas, but leading and trailing blanks are removed.

• The length of a value string is limited to 16 characters.

• The maximum number of values is limited to 256.

Normally, a default value for the xxx.List field should be defined with the symbol in the library using the device symbol editor tool. In this way, the value list will always be available whenever this device type is selected from the library. If the field is defined in only one device on the diagram, the value list will only be available for that device.

Using Script fields

HYPERSIM allows you to call a script (attribute change script) when a given attribute value changes. A script field has the same name as the associated field but with .Script appended. You must be careful not to create loops through scripts, since that may kill the application. When an attribute changes, HYPERSIM first searches for the attribute change script in the object where the change occurred and if the corresponding xxx.Script string is empty, it looks into the design.

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Using Default Position Fields

For device or pin attribute fields that are to be displayed on the schematic, an associated field called a default position field can be created. For example, this mechanism is used to provide default positions for the Name and Part fields used in all standard HYPERSIM libraries. These standard fields can be used as an example.
A default position field has the same name as the associated field but with .Pt (for Point) appended. When a field named xxx.Pt is seen by the program, it uses the values in this field to generate a default position for the xxx field.

Default Position Data Format

• The default position field must contain a sequence of textual values following these rules:

• Two items, an X and a Y position, must be specified, separated by a comma. Leading and trailing non-numeric characters are ignored.

• The X and Y values are each decimal numbers representing an offset from the top-left corner of the device measured in 1/1000. Negative values are allowed (negative is up and left).

• The X coordinate can be optionally followed by an upper case letter indicating horizontal justification, as follows: L for left, M for middle, R for right. The given number specifies the offset to the left, middle or right position of the displayed text. If no letter appears, middle is assumed, i.e. the text will be centered at the given position.

• The X coordinate can be optionally followed by a lower case letter indicating which point on the symbol’s bounding box to use as the reference point, as follows: l for the left edge, m for the midpoint, r for the right edge. The given number specifies the offset from the left, middle or right position of the symbol. If no letter appears, left is assumed.

• The Y coordinate can be optionally followed by an upper case letter indicating vertical justification, as follows: T for top, M for middle, B for bottom. The given number specifies the offset to the top, middle or bottom position of the displayed text. If no letter appears, middle is assumed, i.e. the text will be centered at the given position.

The Y coordinate can be optionally followed by a lower case letter indicating where on the symbol the position is to be measured from, as follows: t for top, m for middle, b for bottom. The given number specifies the offset from the top, middle or bottom of the symbol’s bounding box. If no letter appears, top is assumed.
Some examples of value points are:

Normally, a default value for the xxx.Pt field should be defined with the symbol in the library using the device symbol editor. In this way, the value will be available for setting the default position of the associated field when the device is placed on the schematic.

You can place a symbol on a schematic, position all the displayed attributes in the locations you want them, and then use the Options>Part Type>Save to Lib command to store the symbol back into a library. The Save to Lib command automatically creates .Pt fields for any displayed attributes and saves them with the new definition. See Saving Part Type to Library for more information.

Defining Attribute Fields

All changes in field definitions are done using the Define Attribute Fields command in the Options > Design toolbar. Selecting this command displays the following dialog box:

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To create a new field:

• Select the *New Field* item in the list, if it is not already.

• Type the name of the field in the Field Name box.

• Select one or more of the boxes under Allowed in object types.

• Optionally enter a maximum length.

• Optionally enable any of the other field options.

• Click OK. The new field will now appear in the attribute data entry box for the selected object types.

You should not modify already defined fields for the HYPERSIM template as this may have dangerous consequences and corrupt design data.

Setting Attribute Field Options

When a new field is created using the Define Attribute Fields command a number of options are available which determine how that field will behave in your design. These options are described in the following sections.
Changing any of the following options in a field that has already been used in the design has no effect on items already displayed on the schematic.
To make a temporary change (e.g. to display a field that is not normally displayed) you can use the Duplicate button in the Define Attribute Fields box to create a new field containing the same data but with new display options. This field can be deleted again when no longer needed.
Note the following characteristics of these settings:

Changing the values of any of the option switches for an existing field do not affect any values already in the design. Only new data will be affected. See Temporarily Displaying Attributes for tips on using the Duplicate function to update the way existing data is displayed.

• The name and option settings for most predefined fields are fixed and will be disabled in this box.

• Regardless of changes made in this box, no design data is updated until you click the OK button.

Duplicate, Merge and Delete options

• The Duplicate, Merge and Delete Attribute functions do more than just add or delete a name in the attribute list. They will actually scan the entire design and update the data stored with each object. This makes them very powerful tools for updating your design. First we will review how the functions are invoked, then mention some possible uses for them.

• These three functions are all invoked from the Define Attribute Fields command. No design data is modified until the OK button is clicked in the Define Attribute Fields box.

• When the design is updated, all Duplicates are done first, then all Merges and Deletes. This means that a field can be duplicated, then the original source deleted, all in one invocation of the Define Attribute Fields box.

• There is no guarantee of the order of execution within the Duplicates or within the Deletes and Merges. Therefore, chains of operations (e.g. making a copy of a copy) are not guaranteed to work as expected. If there is any doubt, perform one operation, then exit the Define Attributes Fields box using the OK button, then perform the next operation.

• Each of these operations can result in data being updated throughout a design. and they cannot be undone! For large designs there may be a considerable delay after the OK button is clicked in the Define Attribute Fields box.

Globally Duplicating Attribute Data

The Duplicate operation adds a new field name to the list with characteristics the same as an existing one. It will also optionally duplicate the data stored under that name throughout the design.

• The pre-defined fields in HYPERSIM cannot be renamed or removed. However, you can duplicate them, and the copy will be marked as user-defined, meaning that it can be deleted again or modified in any way.

• A field is duplicated by selecting its name in the field list and then clicking on the Duplicate button in the Define Attribute Fields dialog:

• At this point a box will be displayed allowing you to choose one of the following options:

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Merging Two Existing Attribute Fields

The Merge operation takes two existing attribute field definitions and merges them into one. If a given object (device, signal, pin or design) has values in both of the original fields, the one being renamed takes precedence and the other is lost.
Pre-defined fields cannot be renamed, so they cannot be merged into other fields. You can however merge a user-defined field into a pre-defined one.
There is no explicit button for the Merge operation. Merge is invoked whenever a field is renamed so that its name matches another field's.

The procedure is as follows:

• Click on the field to be renamed in the field list. The data in this field will take precedence when the design is updated.

• Type the new name (i.e. the name of the field you wish to merge to) into the Field Name text edit box.

• Type the Tab key or click on any of the option switches to indicate that you have finished typing.

• A box will be displayed asking you to confirm the merge. Click the OK button:

The actual merging of design data does not take place until you click on the OK button in the Define Attribute Fields box.
You can only merge fields that have similar Allowed in Object Types settings. It means that you cannot merge a signal field into a device field.

Deleting Attribute Field Definitions

The Delete operation removes the selected name from the list of available fields and removes all data values associated with the field throughout the design. Pre-defined fields cannot be deleted. Before deleting any field, verify its documentation or its usage, harmful conditions will result otherwise.

• This operation cannot be undone and should be used with care.

• To delete a field, simply select its name in the field list and click on the Delete button.

• In any case, no design data is updated until the OK button is pressed on the Define Attribute Fields box.

Temporarily Displaying Attributes

The Duplicate function is a convenient method of displaying data temporarily on the schematic. For example, you may wish to display some simulation parameters on the schematic while tracking a particular design problem, even though you don't want them there for the final printout.
To do this:
Select the Define Attribute Fields command (Options> Design).

• Choose the field you wish to display.

• Click on the Duplicate button.

• Click on the Duplicate Data option in the confirmation box.

• Enable the Visible by Default and (if desired) the Show Field Name and Primary options.

• Click the OK button in the Define Attributes box to complete the operation.

The duplicate field will now be displayed on each object in the design. When the duplicate field is no longer needed, it can be removed with the Delete function described above.

Permanently Showing Data Throughout a Design

The Visible by default option in the Define Attribute Fields box normally has no effect on values that already exist in the design. Enabling the option for a field that is already in use affects only future entries. However, the Duplicate and Merge operations can be used to update the display of existing data throughout the design. This is done as follows:

• Select the Define Attribute Fields (Options > Design).

• Select the field to be displayed in the field list.

• Click the Duplicate button.

In the confirmation box, click the Duplicate Data button.

• You now have a copy of the original field: Make sure the newly-created field is selected in the list, then rename it back to the name of the original field. If the original field was Name, the duplicate will be Name1 and we now select Name1 and rename it back to Name. Press the Tab key or select another field name when you are finished typing.

• The Merge confirmation box will appear. Click the OK button.

• Click on the Visible By Default option and any other display options desired.

• Click the OK button to complete the operation

This operation in effect re-enters all the data into the selected field with the new display options.

Merging Dissimilar Designs

The Merge feature is a useful tool when bringing together designs created with different attribute definitions, or when importing designs from other systems or older versions of HYPERSIM.
We strongly recommend reviewing attribute field usage under these circumstances and using the Merge feature to convert all non-standard fields to pre-defined ones where possible. This will make the design more compatible with the standard report formats provided with HYPERSIM and will reduce confusion in future design revisions.

Importing Attribute Definitions

Whenever circuit data is brought into a design, either from a design file, a device library or the clipboard, it is possible that the incoming data contains attribute fields that are not defined in the destination design. This section discusses how HYPERSIM deals with this situation.
In general, HYPERSIM attempts to ensure that an entry exists in the attribute definition table for every field used in the design. When new data is imported, field usage in the imported data is compared to the existing table. Normally, no discrepancies are found and this process is invisible. If any mismatch is found, you will be warned and given a chance to add the new definitions to the table automatically.

Pasting from the Clipboard or Placing a Library Device

In these two cases, HYPERSIM does the following:

• All fields used in the incoming device or circuit scrap are looked up in the design's attribute table.

• Any field that doesn't exist in the design is put on a list to be added.

• Any field that does exist in the design but is incompatible (i.e. different object type or keep with instance settings) is renamed by adding an underscore _ to the name.

• A list of the new fields that will be added is displayed in a warning box. If any of these fields are unexpected, or can be converted to standard fields, the names should be noted at this point. Changes in field usage can be made using the Merge and Delete operations mentioned elsewhere in this chapter.

Predefined Attribute Fields

The following tables list fields that are predefined for each new design that is created from the standard HYPERSIM template. These fields cannot be removed because many of them are used internally by specific HYPERSIM features.
The following information is provided in the table:

More on the usage of these fields can be found in other documentation sections. The documentation of individual devices also contains information on device data storage into attributes.