Using the Electric VLSI Design System

Chapter VI: ADVANCED EDITING

| ## 8: Text |

### Understanding Text

There are a number of ways to place text in a circuit.

- Each unexpanded instance of a facet has text that describes it, and its ports.
- Each exported port has a text label.
- Nodes and arcs can be named (with Get Info) so that they have text on them.
- Certain primitive nodes (such as the Flip-Flop component of the Schematic technology) have text as an integral part of their image.
- It is even possible to create a special node that is only text (with the Text (nonlayout) subcommand of the New Special Object command of the Edit menu, or the Add Verilog Code/Declaration commands of the Simulation Interface command of the Tools menu).

Essentially, then, every piece of text on the display is tied to some node or arc. By understanding the relationships between text and the attached objects, it becomes easy to manipulate that text.

### Selecting Text

The only category of text in the above list that is not selectable is the text that is integral to a node's graphics (i.e. the Flip-Flop). For the rest, you can select and manipulate the text just as you would the object on which the text resides. (Note that port names on facet instances are not selectable: instead, select their name inside of the facet definition.)

Certain types of text are not easily selectable. This is a feature that prevents accidental selection of unwanted text. For such pieces of text, the only way to select them is to use the special select button. By default, the name of an unexpanded facet instance requires this button. However, you can also request that names on nodes and arcs (annotation text) also be difficult to select by unchecking "Easy selection of annotation text" in the Selection Options... subcommand of the Selection command of the Edit menu.

All text is attached to its node or arc at a grab-point. This is the one point on the text that never moves, regardless of the size of the text. The highlighting of selected text varies according to the grab-point. Typically, the highlighting consists of an "X" through the text. This indicates that the grab-point is in the center. If a "U" is drawn in any of four orientations, it indicates that the grab-point is on the side and that the text grows out of the opened end. If an "L" is drawn in any of four orientations, it indicates that the grab-point is in a corner. Finally, the text may be drawn with an "X" but also have four lines that indicate a box at the object edge. This is centered text that clips to the size of its attached object (it is "boxed"). |

### Modifying Text

Like nodes and arcs, text can be moved simply by clicking and dragging. It can be erased with the Erase command of the Edit menu.

There are two ways to change the actual text: in-place editing or with a dialog. In-place editing is done by double-clicking on the text. After the double-click, all of the text is selected. Portions of the text can be selected by clicking over it. To insert or replace text, simply type. When done editing, click away from the text to end the editing mode.

Dialog control of text is done by using the Get Info command of the Info menu. This dialog allows modification of the text, size, grab-point, and even the offset of the grab-point from the attached node or arc. Note that the offset is always relative to the center of the attached object. The size of text can be absolute (given in "points") or one of three relative sizes (which scale with the display). The little arrows next to the grab-point options show where the point of attachment lies on the text. If the text contains more than 1 line, then the only way to change it is to click on the "Edit Text" button, which closes the dialog and enters in-place editing mode. |

The checkbox "Only visible inside facet" requests that the text not be drawn when an instance of the facet is examined. In addition, for text objects (those created with the Text (nonlayout) subcommand of the New Special Object command of the Edit menu) the location of the text will not affect the bounding box of the facet. This means that the text can be placed arbitrarily far outside of the actual layout, and it will not affect the hierarchy.

| For special pieces of text that the system understands, you may get a customized dialog when you double-click. For example, if you double-click over the resistance value of a resistor, a special dialog will appear to set the resistance. To change other information, use the "More..." button to see the general dialog.

### Text Defaults

To change the default size and grab-point of all new text, use the Text Options... command of the Windows menu. This lets you set the default size and grab-point of subsequently created text. In addition, it lets you set "smart placement" of text, which adjusts the grab point according to the environment of the text. This currently only applies to port names, which are placed relative to the arc connecting to the exported node. For example, if a node on the left end of a wire is exported, and the "Smart Horizontal Placement" is set to "Inside", then the text will attach on the left side, causing the label to appear inside of the wire. Finally, this dialog allows you to make text objects (those created with the Text (nonlayout) subcommand of the New Special Object command of the Edit menu) be visible only inside of the facet, and not when instances of the facet are expanded. |

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