ZPL Manually Install a font - zebra-printers

Question

I am trying to manually install a font with ZPL. I have a TTF file and I believe I have the command. The issue is when I try to print with that font nothing gets printed.
I am able to upload the font to the printer with the following command
~DYE:COMIC.TTF,A,T,63040,,AAEAAA.......
Note I am truncating the data section, but I also believe this is where my issue is coming from.
After that command completes I can validate that the font is there by running
^XA^WDE:*.*^XZ
I see the COMIC.TTF font installed, but when I print a label with
^XA^FO50,50^A#N,50,50,E:COMIC.TTF^FDSAMPLE^FS ^XZ
Nothing is displayed. I believe the issue has to do with the font not being uploaded correctly. Any help would be appreciated.

Answer 1

I would like to thank https://stackoverflow.com/a/64333380/634911 for the big hint on how to do this. Instead of using the ~DY command to upload the font I ended up using the ~DU command. I believe they will do the same thing, but I managed to get it to work with the ~DU command.
The big issue that I was having was the encoding of the TTF font file. using the template from the mentioned stackover answer I wrote a quick demo program that encodes a TTF file saves it to the DRAM and is then able to use that file.
using System;
using System.IO;
namespace Font
{
class Program
{
static void Main(string[] args)
{
var dirPath = #"<path to directory> i.e. C:\user\";
var fontName = "comic.ttf";
var filePath = $#"{dirPath}{fontName}";
var data= BitConverter.ToString(File.ReadAllBytes(filePath)).Replace("-", "");
var fileSize = File.ReadAllBytes(filePath).Length;
var zpl =
$#"^XA^CI~DUR:{fontName.ToUpper()},{fileSize},{data}^FO100,0^A#N,100,50,R:{fontName.ToUpper()}^FDTESTSTRING^FS^XZ";
Console.WriteLine(zpl);
}
}
}