Item numbers "read" information from an info point. It is also possible to insert an item number manually, and then supply it with information. An item number block has one attribute more than an info point: the item number value.

The item number value is extrapolated by AutoCAD automatically using the increment defined in the configuration settings. A new item number is assigned the value of the highest existing item number plus the predefined increment. The default AutoCAD increment is 1.

AutoCAD checks constantly that there are no duplicate item numbers in the drawing.

• If any duplicate item numbers are detected, a dialog box to this effect will appear.
• If, when you enter the item number, you use an item number that already exists, a dialog box appears. You can decide here whether you want to accept or change this item number. If you decide to change the item number, AutoCAD will default an item number that is free.

If the drawing comprises several AutoCAD drawing frames, this is taken into account when numbers are assigned. This does not, however, occur automatically. You must select the frame into which you want to insert the item number.

In this example, the drawing only has one frame.

When you choose the function, the following message is issued:

The message line that appears will depend on your BOM configuration settings. In the "Info points" option of the "Item number" section, you can activate either the "Use info points" option, the "Replace with text" option, or the "Suppress" option, and you can make other settings.

Select an info point (P1). A dialog box appears where you can enter new values, or change existing values. Confirm your entries by pressing the ENTER key.

In the From point field, you specify the start point of the item line (P2). The following message appears:

Position the number at a suitable location in the drawing (P3). If you are not happy with the last item line drawn, you can undo it by choosing the "Back" option.

Tools are provided for the item itself ("Arrange" option), and for the appearance of the drawing ("Format" option).