Home  >  Robotics  >  XYZ plotter

HALO XYZ Plotter Simulation

Explore a three-axis XYZ plotter motion system with independent stepper control, homing, end-limit detection, GPIO control, and simulator-based waveform visualization.

Robotics XYZ Plotter 3-Axis Stepper GPIO
Overview Theory Architecture Simulation Source Code Pinout Examples Downloads

Overview

The HALO XYZ Plotter is a 3-axis virtual hardware system designed for learning, simulating, and validating digital control of a plotter-style motion system.

The system provides three independent stepper channels for X, Y, and Z motion. Each axis includes dedicated control signals and hardware limit switches for homing and end-of-travel detection.

Each stepper driver uses ENABLE, DIR, and STEP control signals. Because the required control signals exceed the capacity of a single 8-bit GPIO block, the system distributes the signals across GPIO0 and GPIO1.

Key Features

  • Three independent stepper channels
  • X-axis motion control
  • Y-axis motion control
  • Z-axis motion control
  • ENABLE, DIR, and STEP control signals
  • Home limit switches for all three axes
  • End-limit switches for all three axes
  • Two GPIO ports for control signal expansion
  • Integrated simulator
  • Waveform visualization for debugging motion behavior

Axis Summary

HALO XYZ Plotter Axis Structure
X Axis
Stepper X
→
Y Axis
Stepper Y
→
Z Axis
Stepper Z
→
Plotter

Applications & Use Cases

  • XYZ plotter motion control
  • Stepper motor control experiments
  • Digital motion-control learning
  • Axis homing experiments
  • End-of-travel limit detection
  • GPIO-based motion control
  • Waveform debugging
  • Educational robotics and embedded control
HALO XYZ Plotter Control Flow
Controller
→
GPIO0 / GPIO1
→
X / Y / Z
→
Stepper Drivers
→
XYZ Plotter

Theory

The HALO XYZ Plotter uses three independent stepper-driven axes to control movement along the X, Y, and Z directions.

Each axis is controlled using three digital signals: ENABLE, DIR, and STEP. Hardware HOME and END switches provide position boundary detection.

Motion Control

XYZ Motion Control
X Axis
+
Y Axis
+
Z Axis
→
Plotter Position

Stepper Control 

ENABLE → Enables the stepper driver

DIR    → Selects the direction of motion

STEP   → Generates step pulses

HOME   → Detects the home position

END    → Detects the end-of-travel position

Architecture

The HALO XYZ Plotter consists of a controller, two GPIO register blocks, three stepper motor drivers, three motion axes, and hardware limit switches.

Controller
→
GPIO0
→
X Axis

GPIO0
→
Y Axis
→
Stepper Y

GPIO1
→
Z Axis
→
Stepper Z

Control Signals

  • ENABLE — Enables the stepper motor driver
  • DIR — Selects the direction of axis motion
  • STEP — Generates step pulses
  • HOME — Detects the axis home position
  • END — Detects the axis end limit

Simulation

Run the HALO XYZ Plotter simulation and observe independent X, Y, and Z axis movement.

The simulator provides motion behavior visualization and waveform information for debugging the digital control signals.

Launch Simulation

Source Code

Example GPIO configuration for the HALO XYZ Plotter controller.

GPIO0 Configuration 

// GPIO0: Outputs on bits 0,1,2,5,6,7
// Inputs on bits 3,4

WRITE_REGISTER(0x40000000, 0xE7);

GPIO1 Configuration 

// GPIO1: Outputs on bits 2,3,4
// Inputs on bits 0,1,5,6
// Bit 7 unused

WRITE_REGISTER(0x40000400, 0x1C);

X Axis Control 

X_ENABLE → Enable X stepper
X_DIR    → Select X direction
X_STEP   → Generate X step pulse
X_HOME   → Detect X home
X_END    → Detect X end limit

Y Axis Control 

Y_ENABLE → Enable Y stepper
Y_DIR    → Select Y direction
Y_STEP   → Generate Y step pulse
Y_HOME   → Detect Y home
Y_END    → Detect Y end limit

Z Axis Control 

Z_ENABLE → Enable Z stepper
Z_DIR    → Select Z direction
Z_STEP   → Generate Z step pulse
Z_HOME   → Detect Z home
Z_END    → Detect Z end limit

Pinout

GPIO register mapping for the X, Y, and Z stepper controlled axes and their hardware limit switches.

GPIO0

Bit 0
X_ENABLE
Bit 1
X_DIR
Bit 2
X_STEP
Bit 3
X_HOME

Bit 4
X_END
Bit 5
Y_ENABLE
Bit 6
Y_DIR
Bit 7
Y_STEP

GPIO1

Bit 0
Y_HOME
Bit 1
Y_END
Bit 2
Z_ENABLE
Bit 3
Z_DIR

Bit 4
Z_STEP
Bit 5
Z_HOME
Bit 6
Z_END
Bit 7
Unused

Register Addresses

GPIO0 MODE
0x40000000
GPIO0 IN
0x40000004
GPIO0 OUT
0x40000008

GPIO1 MODE
0x40000400
GPIO1 IN
0x40000404
GPIO1 OUT
0x40000408

Examples

Example exercises for the HALO XYZ Plotter.

  • Move the X axis using stepper pulses
  • Move the Y axis using stepper pulses
  • Move the Z axis using stepper pulses
  • Perform X-axis homing
  • Perform Y-axis homing
  • Perform Z-axis homing
  • Detect X-axis end limits
  • Detect Y-axis end limits
  • Detect Z-axis end limits
  • Generate coordinated XYZ motion
  • Analyze stepper control waveforms
  • Debug motion behavior using the waveform viewer

Downloads

Download simulation files, source code, documentation, GPIO configuration, and waveform files for the HALO XYZ Plotter.

Download Files