zpl.tools
RFID

^WV - Configure RFID Write Verify

Turns on or off the read-back check the printer performs after encoding a tag.

Some tag manufacturers pre-program their transponders with known test data. ^WV makes the printer check for it — hex A5A5 in the first two bytes — before it encodes. It catches a tag already written or an unexpected tag. It is off by default.

Syntax

^WVe

Support

Recognised, deliberately skippedparsed: none · state: none · rendered: none

Accepted and skipped, because it configures the printer rather than the label. It cannot change the rendered output, and Labelary skips it too.

Decides whether the printer reads a tag back after it writes. Neither the write nor the read-back happens here. The renderer does not parse this command. It reports IGNORED_COMMAND at info severity, which does not reach X-Warnings. Labelary is also silent, so the rendered label is identical in both engines and with or without the command. — not pinned by a test

Labelary renders this command.

Parameters

eEnable write verifyoptional · Y or N

Whether the printer checks, before it encodes, that the tag holds hex A5A5 in its first two bytes, the test data some manufacturers pre-program. The guide notes the setting is not persistent from label to label.

Default
N
Invalid value
not documented, and we have not measured it. The renderer does not parse this command or validate its arguments. The guide does not state what a printer does with an out-of-range value.
Test coverage
No documented value is exercised by a test (Y, N).
Y
Verify before writing.
N
Do not verify. (default)

Behavior

The setting is not persistent. It applies to the format that carries it and resets for the next one, so a batch needs it in every format. ^WT parameter v performs the same check for a single write.

The check happens inside the transponder exchange and never appears on the label.

Example

Turning write verify on above a single line of text:

^XA
^WVY
^FO50,50^A0N,30,30^FDwrite verify on^FS
^XZ

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