Specifications

36 Chapter 3—Advanced Schematic Editing
 If you select a bus line, then pull down the Schematic menu and select
the Get Info command. The displayed info box will show a list of the
signals currently contained in the bus.
 A given signal can be present only in one bus. If you attempt to connect
together two signals in different busses, a warning box will be
displayed and the connection will be canceled.
 A bus can be created by drawing the bus lines first, then creating the
breakouts to attach, or by creating a breakout and extending the bus
line starting at the bus pin. Bus lines are drawn or extended using
exactly the same techniques as for signals, except that the Draw Bus
command or cursor is used instead of Draw Signal.
Properties of Breakouts
Signals are attached to a bus via a special type of device symbol called a
“breakout.” It is not legal to attach a signal line directly to a bus line. If a sig-
nal line touches a bus line, no connection will be made. In LogicWorks, a
breakout is treated as a device with certain special properties. This means
that it can be placed in any desired orientation, moved, duplicated, etc., using
any of the device editing features available. A typical breakout appears as
follows:
Any breakout can always be attached to any bus. When a breakout is
attached that contains signals unknown in that bus, the signals are implic-
itly added to the bus. For example, suppose we want to add control signals
to the above circuit. We could create a breakout containing only the new
signals, as follows:
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