Deep Dive into HP’s PCL Language

You ever send a document to the printer and wonder what black magic happens inside? Welcome to the world of Printer Command Language (PCL)—HP’s way of making sure your documents don’t turn into a scrambled mess.

A Brief History of PCL

Before we get into the nitty-gritty, let’s take a quick trip down memory lane. PCL was developed by Hewlett-Packard (HP) in 1984 to control laser printers, starting with the HP LaserJet. Unlike PostScript (which we’ll compare later), PCL was designed to be a simpler, more efficient way to communicate with printers.

Here’s how it all connects:

• HP created PCL as a lightweight alternative to complex printer languages.
• It became the de facto standard for office and consumer printers.
• Over time, it evolved, with different versions adding more features like fonts, color printing, and better graphics.

If you want to geek out more, check out:

• Wikipedia: PCL
• HP’s official PCL documentation

How PCL Works

PCL is a page description language that tells your printer how to lay out text and graphics on a page. Unlike PostScript, which is Turing-complete (meaning it’s practically a full programming language), PCL is more straightforward.

Example 1: Basic PCL Commands

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E            # Reset Printer
&l1O        # Set orientation to portrait
(s10H       # Set font size to 10pt
Hello, PCL!

• E - Resets the printer.
• &l1O - Sets the page orientation to portrait.
• (s10H - Sets font size to 10pt.
• "Hello, PCL!" - Prints text.

Unlike PostScript, which processes everything before rendering, PCL processes commands line by line, making it faster for simple printing tasks.

Debugging PCL

PCL debugging is a bit tricky since most modern tools are geared toward PostScript. However, you can test PCL without printing using:

1. HP Print Preview Tools (Some HP utilities allow you to preview PCL output.)
2. Using a PCL Viewer such as:
   • PCL Parser
   • GhostPCL
3. Converting PCL to PDF for preview:

   1	pcl6 -sDEVICE=pdfwrite -sOutputFile=output.pdf input.pcl

Testing PCL Without a Printer

Using GhostPCL

GhostPCL is part of Ghostscript and allows you to interpret and render PCL files.

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gpcl6 input.pcl

This lets you check output before sending it to the printer, saving time (and paper).

Essential PCL Commands with Examples

Example: Printing a Bold Header

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E            # Reset Printer
(s1B       # Bold text on
Header Line
(s0B       # Bold text off
Normal Text

Example: Printing in Color (PCL 5+)

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E            # Reset Printer
*rB         # Begin raster graphics
*v255a0b0C  # Set color to red (RGB)
Hello in Red!

PCL 5 introduced basic color printing, though it’s nothing compared to what PostScript can do.

1. Setting Margins

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&l2E       # Set top margin at 2 lines

2. Changing Line Spacing

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&l6D       # Set line spacing to 6 lines per inch

3. Drawing a Box (PCL 6+)

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*c100a100B # Draw a 100x100 box

4. Printing a Barcode (PCL 5+)

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(s1P(s4099T12345678

5. Rotating Text

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&a10R      # Rotate text 10 degrees

6. Changing Paper Size

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&l26A      # Set paper size to A4

7. Printing Underlined Text

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&d0DHello &d@ World

8. Changing Text Justification

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&a1J       # Set text justification to centered

9. Creating a Header and Footer

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&l0LHeader
&l8LMain Text
&l66LFooter

10. Using Macros for Repeating Content

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&f1X       # Define Macro

PCL vs. PostScript: The Printer Wars

So how does PCL compare to PostScript? Let’s break it down:

Why PCL is Faster but Simpler

• PCL interprets commands line by line, making it faster for standard office documents.
• PostScript is a full programming language, meaning it processes the entire page before rendering, leading to higher quality but slower performance.

When to Use What?

• PCL is great for office printing, invoices, and documents.
• PostScript is ideal for graphic design, PDFs, and publishing.

Learn More

• Wikipedia: PCL
• Wikipedia: PostScript
• HP PCL Documentation