HPGL Protocol: Understanding Serial Communication

HPGL (Hewlett-Packard Graphics Language) is the command set that most vinyl cutters, laser cutters, and plotters understand. CutCutBoom leverages HPGL to send precise cut instructions to your hardware.

What Is HPGL?

HPGL is a printer/plotter control language developed by Hewlett-Packard in the 1970s. Despite its age, it’s still the standard for cutting machine communication.

Common HPGL commands:

• PA (Plot Absolute): Move pen to X,Y coordinates
• PD (Pen Down): Lower the blade to cut
• PU (Pen Up): Raise the blade
• VS (Velocity Select): Set cutting speed

How CutCutBoom Uses It

1. User creates a job (vector path, speed, pressure)
2. Job is converted to a sequence of HPGL commands
3. CutCutBoom sends commands over serial port (USB, COM port, etc.)
4. Machine executes commands in real-time
5. Operator monitors progress, can emergency-stop at any time

Serial Connection

Most machines connect via:

• USB-to-Serial adapters (modern machines)
• COM ports (older machines)
• Direct USB (newer proprietary interfaces)

CutCutBoom autodetects available ports and allows manual port selection.

The Power of Knowing HPGL

Understanding HPGL means you can:

• Debug failed jobs
• Create custom macros
• Troubleshoot serial communication
• Integrate with other HPGL-compatible software