Hints & Tips

Q: I often use the temporary reference point, but I would like to see both absolute coordinates and relative coordinates, without toggling the reference point on and off.

A: The menu command Measure>> Coordinate Axes toggles the display of the coordinate axes. They are shown along the upper and left borders of the layout window. The current cursor position is shown by running marks on these axes. Therefore if you switch the axes on and set a reference point, you may see the relative cursor position at the Metric bar, as well as the absolute cursor position at the coordinate axes, see Figure 1. Cursor cross-hairs may be helpful in this case as well.

Figure 1.

 

Q: Can I perform a check for polygons touching by corners using your Savage DRC system? (See Figure 2.)

A: The required check looks somewhat complex:

(* CHECKS FOR CORNER TOUCHING ERRORS *)

(* NOTE: merge the IN layer only if it is not already merged *)

Merge:

Layer = IN,
LayerR = &IN_Merged(1);

OutDistance:

Layer = &IN_Merged,
Type = LE,
Value = 0.00um;

Width:

Layer = &IN_Merged,
Type = LE,
Value = 0.00um;

The reason is that there is some discrepancy in merging operation. In Expert two touching boxes are never merged into one figure. In Savage they are sometimes merged into an 8-shaped polygon, so you need to check both for zero outdistance and for zero width. This discrepancy will be fixed in one of the subsequent releases of Savage system.

Figure 2.

 

Q: Windows NT task manager shows me that DRC Guard takes almost 100% of CPU time. Naturally, this worries me.

A: When DRC Guard performs checks, it is supposed to use 100% of processor time. When DRC Guard enabled but idle, you can still notice that processor is about 100% busy. This happens because the error mark drawing function of DRC Guard runs in background.

Even if there are no errors, this function can load the processor to 100%. But this is not to be worried about. This cycle works only when Expert and other WinNT applications are idle. When you start using Expert, DRC Guard drawing is stopped and Expert performance is not affected. Moreover, this drawing is stopped when some other application is activated, so the performance of WinNT and other applications are not affected.

 

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