I've a ZQ520 printer and I started learning ZPL from here.
I need to print some information in different style, to highlight important data. The problem is that I can't find the instruction to print in grayscale.
I'm searching something like this:
^XA
^FO50,50^ADN,18,10^FDBlack text^FS
^FO50,100^ADN,18,10^GS25^FDGrayscale text^FS
^XZ
Where ^GS means Gray Scale and not Graphic Symbol.
The ZQ520 does not support grayscale. If you are printing from a mobile device your best bet is to create a graphic with the gray text. You can then use the Zebra SDK to convert the bitmap to a form. The SDK will dither the image making it appear grayscale on the printer.