Specifications

The format for the ^GB instruction is:
^GBw,h,t,c
where
^GB = Graphic Box
w = Width of Box (in dots
Default value: Value used for thickness or 1 dot
Minimum value: 1 dot
Maximum value: 9999 dots
h = Height of Box (in dots
Default value: Value used for thickness or 1 dot
Minimum value: 1 dot
Maximum value: 9999 dots
t = Thickness of Line (in dots)
Default value: 1 dot
Minimum value: 1 dot
Maximum value: 9999 dots
c = Line Color
Default value: B = Black
Other value: W = White
For the w and h parameters, keep in mind that printers will have a
default of 6, 8, or 12 dots/millimeter. This comes out to 153, 203 or
300 dots per inch. To determine the values for w and h, figure out the
dimensions in millimeters and multiply by 6, 8 or 12.
ZPL II COMMAND REFERENCE 231
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