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I'm looking at a circuit diagram for the ChipWhisperer, which is a tool for power analysis and glitch attacks. You can grab the full circuit schematic as a PDF, but here's an excerpt:

Circuit diagram

What do those alphanumeric suffixes mean after the slash in the cross-reference names? Elsewhere in the diagram these signals are referred to by name, but the suffix is usually different despite it being the same signal.

Polynomial
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    Looks like a PAGE#.COORDINATES reference, though the pages do not show the 5H like number axis on them. Perhaps the editor does in the bottom margin. Example... you will find the other end of SAM_CS1 on page 7... – Trevor_G Oct 16 '17 at 22:42
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    @Trevor Spot on with the page reference! Sheet 7 has a reference to `SAM_CS1/2.3H`, and the screenshot above came from sheet 2. I guess `5H` and `3H` are on-page coordinates, although there's no grid on the PDF schematic. – Polynomial Oct 16 '17 at 22:48

1 Answers1

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From Eagle help file 'Editor commands - LABEL':-

Cross-reference labels

If the optional keyword XREF is given, the label will be a "cross-reference" label. Cross-reference labels can be used in multi-sheet schematics to indicate the next sheet a particular net appears on...

The format in which a cross-reference label is displayed can be controlled through the "Xref label format" string, which is defined in the "Options/Set/Misc" dialog, or with the SET command. The following placeholders are defined, and can be used in any order:

%F enables drawing a flag border around the label

%N the name of the net

%S the next sheet number

%C the column on the next sheet

%R the row on the next sheet

The default format string is "%F%N/%S.%C%R".

The column and row values only work if there is a frame on the next sheet on which the net appears... If the net appears only on the current sheet, no cross-reference is shown

So TDI/3.2D means net TDI goes to sheet 3 column 2 row D.

Bruce Abbott
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  • Just wanted to add to Bruce's answer that this only works in the options tab of the schematic window. – Tim May 05 '20 at 18:19