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What is first bytes for first three commands

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
25/100
Issue type
Documentation
Clarity
Mostly clear
Activity status
Stale
Tech stack
csharp, nodejs, typescript
Domain
embedded-iot

Research direction

Start with the raster() entry point and the GSV0_FORMAT lookup shown in the issue. Trace how header, raster.width, and raster.height are encoded, then verify the resulting bytes for a 384x384 image against the printer protocol or existing tests. Done means documenting the three byte sequences clearly for the StarTUP 900 use case.

Written by the indexing model from the issue text.

Description

I don't know TypeScript but I very need to develop print Image on StarTUP 900 printer.
I use .net/C# lang.
There is function from this project:

raster(image: Image, mode: RasterMode = 'NORMAL') {
    if (!(image instanceof Image))
      throw new TypeError('Only escpos.Image supported');
    mode = utils.upperCase(mode);
    if (mode === 'DHDW' ||
      mode === 'DWH' ||
      mode === 'DHW') mode = 'DWDH';
    const raster = image.toRaster();
    const header = _.GSV0_FORMAT[`GSV0_${mode}` as const];
    this.buffer.write(header);
    this.buffer.writeUInt16LE(raster.width);
    this.buffer.writeUInt16LE(raster.height);
    this.buffer.write(raster.data);
    return this;
  };

So, can anybody send me bytes for these three commands:

this.buffer.write(header);
this.buffer.writeUInt16LE(raster.width);
this.buffer.writeUInt16LE(raster.height);

???
In the case when Image has size 384x384 pixels

Dominant language
TypeScript
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