How to Get Consistent Measurement Units In Various Inspector Windows

The x,y coordinate display on the bottom line of the PCB layout screen can be set to display in inches, millimeters or pixels. That is good.

The inspector window for the PCB shows the board size in millimeters.

The Hole inspector window show the coordinates in inches.

How can I set the hole coordinates to millimeters OR the board size to inches so they are consistent?

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Click on the units icon and it will change units between in, mm and px (click on the red arrow):

change to mm

Same with pcb:

to mm

One note: the numbers are converting from some coordinate system to in and mm, so entering 1.00000 may get you 1.0003 instead of 1 as you would expect. This is I believe reported as a bug, but as far as I know hasn’t yet been fixed (and it may be too much work to fix!)


AHA! I had to shrink the layout window to see that option.


I don’t think it is possible to fix. With that number of digits, you are hitting rounding limits for the calculations. With internal units in mm, there just is not an ‘exact’ value for 1 inch. What happens is that the entered 1 inch is converted into the nearest (I believe) mm value, then that is converted back to the nearest fractional inch value for display. Since neither conversion is ‘exact’ (when done in binary), the lowest digit is not consistent. The only ‘fix’ would be to do the conversion calculation with an extra digit of precision compared to the number if digits displayed (or entered). That would ‘hide’ the final digit that is (looks) inaccurate for what was requested.

Maybe not entirely, but I’d like to see it better than it currently is. Here I placed two resistors, then set each x in inspector to 3.2in

the x values displayed are slightly different (and not what was entered!) Then I moved each via the increment button on the x coord and again they are slightly different (not a significant amount, but an annoying amount!) I would rather see (as you suggest) an extra digit or more probably the current precision but with the last digit rounded up or down as much as needed so the displayed value is consistent. I think that is going to be the least work and the smallest change than trying to add more precision to the calculation which is likely to be a big change. In truth this is visually annoying rather than incorrect (the error value is small!) and thus may be low priority, but it is very annoying when trying to align things on an exact boundary! It also happens even on px (which should be the finest resolution of the three) perhaps indicating the actual units are something finer than px (and it is unclear what the px value is, perhaps 72DPI from early Illustrator?)