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Terminal config diff – compare two nexo XML files

Paste or load two terminal config files in XML (blocks e0 to f2): the comparator matches records by their business key (AID, RID, TAID, BIN…), tells a simple move from a real add/delete, and decodes bit-level fields (terminal capabilities, TAC, nexo parameters). Identical blocks stay collapsed.

Everything runs in your browser. Pasted or loaded files are never sent to a server - parsing and diffing run in client-side JS only. Useful since these files often contain real merchant/acquirer identifiers.

File A

before

File B

after

A nexo tag cannot be read without its block

This is the main trap in these files, and nothing on screen warns you about it: inside a constructed block, DFxx tags are local to that block. The same tag means something entirely different from one table to the next. A decoder that resolves tags flatly gets it wrong, silently.

Three examples straight from the specification:

DF03 is Supported Services in the Application Profile Selection Table, CA Public Key Algorithm Indicator in the CA Public Key Table, and Application Label in the default kernel per AID table.
DF01 has fourteen different meanings depending on the block: profile AID, terminal RID, acquirer number, limit set ID, DCC prefix…
DF10 on its own is Service Settings, but DF10 inside the selection table is Application Profile Kernel ID. Same tag, two definitions, in the same file.

See every meaning of a tag:

Source: data dictionary of , entry tables of the constructed blocks. Labels stay in normative English: these are the identifiers you use to find the row in the specification.