Plain English

Runs a printhead element test and treats failures as fatal — the printer stops and reports an error if any dots are bad. Stricter than ~JO.

When to use

In quality-critical applications where a single bad printhead dot is unacceptable (pharma, compliance labels).

Syntax

~JN

Example

~JN

Run fatal head test (stops on failure)

Try it in the playground View all ZPL commands