Data Sheet

PCB Layout
87
The co-ordinates can be in imperial or metric units as set by the Metric (default key mapping 'M')
command. You can also set a false origin using the Origin command (default key mapping 'O')
in which case the co-ordinates change colour from black to magenta.
The dot grid on the Editing Window can be toggled on and off using the Grid command, or via
its keyboard shortcut (by default this is ‘G’). The spacing of the dots normally reflects the current
snap setting, except when zoomed out. In this case, the dot spacing is set to a suitable multiple
of the snap spacing.
The PCB Layout can be set to display an X cursor at the position to which it has snapped the
pointer through the X-Cursor command, default key mapping is 'X'.
We’ll become familiar with all of these items and use them regularly as we work through
placement and routing of the board.
Navigation
Navigation of the layout (middle mouse zoom, panning, keyboard shortcuts, etc.), is identical to
the Proteus schematic capture package. Refer to the Proteus Getting Started Guide or the
Proteus reference manual for more information.
Visual Aids to Design
The PCB Layout package will use visual effects to help you understand what is happening
during board layout. There are two principle techniques:
Proteus will ‘twitch’ an object when that object is under the mouse and the selection filter
enables selection of that object type. This serves to identify when an object is ‘hot’.
Proteus provides dynamic cursors which change to identify what a left click will do at any given
time (place an object, select an object, move an object, etc.). A list of cursor types is shown
below.
Cursor
Description
Standard Cursor
Placement Cursor - Left click will place and object according to mode.
Selection Cursor - left click will select the object under the mouse.
Movement Cursor - left drag will move the object selected.
Throughout this tutorial – and indeed whenever you are working in the Layout module – you
should make use of these visual indicators to as an aid to understanding the software.
Proteus 8 includes a multi-level ‘undo’ and ‘redo’ system via the shortcut keys
CTRL+Z and CTRL+Y respectively. If you make mistakes throughout the tutorial
remember that you can unwind as many times as you need to!