Datasheet

4. General ISO 14443A Commands
This list gives an overview of the existing commands that can be used with any transponder
that is based on ISO14443A, including all MiFare dialects. Any commands that are specific
to a certain type of MiFare-Type can be found in the next chapter.
Command Name Description
INV Inventory Returns all UIDs from tags in read range
SEL Select tag Selects a tag
RDT Read data Get data from tag
WDT Write data Write Data to a tag
Table 4: Overview of general ISO 14443A commands
4.1. Inventory (INV)
This command returns all UIDs from ISO/IEC 14443-1 to 3 compatible transponder, which
are in the read range of the reader. Only single and double UIDs are supported (all types of
ISO14443A known today). The length of the response can either be 4 bytes (single) or 7
bytes (double). Triple UIDs will be supported as soon as there are tags with this kind of UID.
Instruction:
INV<CR>
Response, if successful:
The UIDs, separated by a carriage return:
UID1<CR>
UID2<CR>
…
The end is marked by the line:
IVF<SPACE>[Count] (Count is the number of transponders found)
Example:
INV<CR>
Response:
C22E5732<CR>
328DA79C<CR>
metraTec MiFare Protocol Guide Page 15 of 38