~DN - Abort Download Graphic
Cancels a graphic download that is in progress.
~DN exists for a state a rendering API never enters. A printer that receives a
~DG or ^GFB payload enters graphics mode and reads raw bytes until the declared count is
complete; ~DN returns it to normal mode. The renderer parses the command and ignores it, so no pixel of the output
changes.
Syntax
~DNSupport
Accepted and skipped, because it configures the printer rather than the label. It cannot change the rendered output, and Labelary skips it too.
The renderer accepts it and does nothing. A download is complete or absent by the time the parser reads the label, so nothing remains to abort. — not pinned by a test
Labelary renders this command.
Parameters
~DN takes no arguments.
Behavior
When the renderer parses a format, every download in it is already complete or
already truncated, so nothing remains to abort. The renderer accepts ~DN and
ignores it wherever it appears. Labelary ignores it too, and a label that carries it
renders identically in both engines.
Two facts still hold on a printer. To stop a download in progress, the host must stop
the transmission: ~DN clears the ~DG that waits, and does not unsend bytes. A
caret or a tilde inside a graphic payload also ends that payload, which is why a
~DG or ^GFB with too large a byte count swallows the commands after it.
Tested behavior
Example
~DN between two labels, with no effect on either:
^XA
~DN
^FO50,50^A0N,30,30^FDprints as if the ~DN^FS
^XZ
Related commands
~DGDownload GraphicDownloads an ASCII-hex bitmap into printer memory as a `.GRF` object.