More About Editing

In the Editing menu there are commands for doing large-scale circuit editing that would be unreasonable with just the basic mouse motions:

Press Editing, drag to Delete, release left mouse button. Now when you move up into the drawing area, the cursor is shaped like a pair of scissors. You can now delete individual things by touching them (with the point where the blades of the scissors cross), or you can delete everything in a rectangular region by pressing at one corner of the region and dragging to the opposite corner. Press the right button to exit Delete mode. You can also press the "d" key to get the Delete mode scissors. Due to an intermittent bug, you may need to click the right button a second time for the scissors to appear.
After you have deleted a group of objects, you can select Paste to "paste" down copies of what was in that region. The Paste command highlights the region that was actually deleted; you can paste back in there for a simple "undelete," or you can paste other places for moving or replicating a chunk of the circuit. This is also on the "*" key.
This is similar to Delete, except that it doesn't actually delete the contents of the rectangle. It is for making copies of something without disturbing the original. After you have copied your object or area of objects, you are automatically switched into Paste mode. This is also on the "/" key.
Move an area. This command is like a Delete followed by a Paste; it moves an object, or all the objects in a given area, to a new location. It is also on the "m" key. Note that the pressing "m" and tapping on a wire moves the wire in a different (often useful) way than simply grabbing the wire.
Implicit Move/Copy
Pressing in empty space and dragging out a box automatically does a combination Move and Copy command. The first place you select moves the contents of the box to that place; if you press at additional places, extra copies are drawn there.

Loading and Saving Circuits

To save your circuit, select Save in the Misc menu, then type the file name to use. It's a good idea to hit Shift-S, or type ":save", periodically to save the circuit under the previous name if any changes have been made. ":save" with no file name argument saves all pages which have been editing back into their original files. Circuits are saved in files ending with ".lgf" (for Log Format). The previous version of the file is backed up under the same name but with ".lfo".

To load a circuit you have saved before, select Load from the Misc menu, and type the name of the file you wish to load. Analog saves the complete simulation state along with the circuit, but you may want to do a RESET after loading anyway.

Annotating Circuits

The Labels command in the Frills menu lets you add text labels to your diagram. Select Labels, type the label you want, then grab it and drag it, as usual, into place. You can edit a label by tapping it, then using the keyboard. Labels generally have no effect on the simulation, but they make plots look much nicer. Also, certain tools such as Logntk and the Digital Log hierarchical simulation gates can read the labels for additional information about the circuit.

The Boxes command in the Frills menu adds yellow dashed boxes to the diagram, again for cosmetic purposes only. Once you're in Boxes mode, you can drag out boxes in the usual fashion. To edit boxes, grab a corner for reshaping or an edge for moving. Both labels and boxes can be deleted by throwing them off the bottom corners of the screen.

Visual Aids for Editing

The Grid command in the Cursor menu switches between the usual arrow cursor and a cross-hair cursor which is useful for aligning things.

The Yardstick command in the Frills menu lets you draw an arrow on the screen which you can use to check the geometric arrangement of objects on the screen. The yardsticks are not "real"---they go away when you refresh the screen. You can also press the "y" key to get a yardstick.


If you select Status from the Misc menu, you get a set of screens describing various aspects of the Log system. Move from screen to screen with the arrow keys. The first screen includes the date and time, amount of memory free (approx.), plus various other stuff. Later screens display the status of the Log editing buffers and keyboard mappings, then there is a screen for the Lplot program (that handles the Plot command), and for the analog simulator.

john [dot] lazzaro [at] gmail [dot] com