Print System Skill

Complete reference for Canon Selphy CP1500 printer integration via CUPS on Raspberry Pi 5.

Quick Reference

Setting	Value
Printer Model	Canon Selphy CP1500
Connection	USB
Paper Size	4x6 inch (Postcard)
Resolution	300 DPI
Print Quality	Maximum
Driver	Gutenprint or CUPS-builtin

CUPS Configuration

Installation

bash

# Install CUPS
sudo apt-get install cups cups-bsd printer-driver-gutenprint

# Add user to lpadmin group
sudo usermod -a -G lpadmin pi

# Enable web interface (optional)
sudo cupsctl --remote-admin

Printer Setup

bash

# List available printers
lpstat -p -d

# Add Canon Selphy (after USB connection)
sudo lpadmin -p Canon_Selphy_CP1500 \
  -E \
  -v usb://Canon/SELPHY%20CP1500 \
  -m everywhere

# Set as default
sudo lpadmin -d Canon_Selphy_CP1500

# Set default options
sudo lpadmin -p Canon_Selphy_CP1500 \
  -o media=na_index-4x6_4x6in \
  -o print-quality=5 \
  -o ColorModel=RGB

CUPS Web Interface

•URL: http://localhost:631
•Admin: https://localhost:631/admin
•Jobs: https://localhost:631/jobs

Print Commands

Submit Print Job

bash

# Print file
lp -d Canon_Selphy_CP1500 /path/to/image.jpg

# Print with options
lp -d Canon_Selphy_CP1500 \
  -o media=na_index-4x6_4x6in \
  -o fit-to-page \
  -o print-quality=5 \
  /path/to/composite.jpg

# Print multiple copies
lp -d Canon_Selphy_CP1500 -n 2 /path/to/image.jpg

Job Management

bash

# List all jobs
lpstat -o

# List jobs for specific printer
lpstat -o Canon_Selphy_CP1500

# Cancel specific job
cancel 123

# Cancel all jobs
cancel -a

# Cancel all jobs for printer
cancel -a Canon_Selphy_CP1500

Printer Status

bash

# Check printer status
lpstat -p Canon_Selphy_CP1500

# Detailed status
lpstat -t

# Check if printer is accepting jobs
lpstat -a Canon_Selphy_CP1500

# Check printer reasons (errors)
lpstat -p Canon_Selphy_CP1500 -l

Print Job States

State	Description
`pending`	Job queued, waiting
`pending-held`	Job held, needs release
`processing`	Currently printing
`stopped`	Paused
`canceled`	User cancelled
`aborted`	System aborted (error)
`completed`	Successfully printed

Error Handling

Printer State Reasons

Reason	Meaning	Retryable
`none`	No issues	N/A
`media-needed`	Out of paper	Yes
`toner-low`	Ink/ribbon low	Yes
`toner-empty`	Ink/ribbon empty	Yes
`cover-open`	Door open	Yes
`offline`	Not responding	Yes
`paper-jam`	Paper jammed	No (manual)
`other`	Unknown issue	Maybe

Check Printer Errors

bash

# Get printer state reasons
lpstat -p Canon_Selphy_CP1500 -l | grep -i reason

# Via CUPS API
curl -s http://localhost:631/printers/Canon_Selphy_CP1500 | grep -i state

Python CUPS Integration

Using pycups

python

import cups

# Connect to CUPS
conn = cups.Connection()

# Get printers
printers = conn.getPrinters()
for name, attrs in printers.items():
    print(f"{name}: {attrs['printer-state-message']}")

# Get default printer
default = conn.getDefault()

# Print file
job_id = conn.printFile(
    printer='Canon_Selphy_CP1500',
    filename='/path/to/composite.jpg',
    title='PhotoBooth Print',
    options={
        'media': 'na_index-4x6_4x6in',
        'print-quality': '5',
        'fit-to-page': 'true',
    }
)
print(f"Job ID: {job_id}")

# Check job status
job_attrs = conn.getJobAttributes(job_id)
print(f"State: {job_attrs['job-state']}")

Using subprocess (fallback)

python

import subprocess

def print_image(image_path: str, copies: int = 1) -> int:
    """Print image via lp command."""
    result = subprocess.run([
        'lp',
        '-d', 'Canon_Selphy_CP1500',
        '-n', str(copies),
        '-o', 'media=na_index-4x6_4x6in',
        '-o', 'print-quality=5',
        '-o', 'fit-to-page',
        image_path
    ], capture_output=True, text=True)

    if result.returncode == 0:
        # Extract job ID from output
        # Output format: "request id is Canon_Selphy_CP1500-123 (1 file(s))"
        job_id = int(result.stdout.split('-')[-1].split()[0])
        return job_id
    else:
        raise PrintError(result.stderr)

def cancel_job(job_id: int) -> bool:
    """Cancel print job."""
    result = subprocess.run(['cancel', str(job_id)], capture_output=True)
    return result.returncode == 0

def get_printer_status() -> dict:
    """Get printer status."""
    result = subprocess.run(
        ['lpstat', '-p', 'Canon_Selphy_CP1500', '-l'],
        capture_output=True, text=True
    )

    status = {'online': False, 'state': 'unknown', 'message': ''}

    if 'idle' in result.stdout.lower():
        status['online'] = True
        status['state'] = 'idle'
    elif 'printing' in result.stdout.lower():
        status['online'] = True
        status['state'] = 'printing'
    elif 'disabled' in result.stdout.lower():
        status['state'] = 'disabled'

    return status

Troubleshooting

Printer Not Found

bash

# Check USB connection
lsusb | grep Canon

# Restart CUPS
sudo systemctl restart cups

# Check CUPS error log
tail -50 /var/log/cups/error_log

Jobs Stuck in Queue

bash

# Check job status
lpstat -o

# Cancel all stuck jobs
cancel -a

# Restart CUPS
sudo systemctl restart cups

# Re-enable printer if disabled
cupsenable Canon_Selphy_CP1500
cupsaccept Canon_Selphy_CP1500

Print Quality Issues

bash

# Set maximum quality
lpadmin -p Canon_Selphy_CP1500 -o print-quality=5

# Verify paper type matches
lpstat -p Canon_Selphy_CP1500 -l

CUPS Service Issues

bash

# Check CUPS status
sudo systemctl status cups

# View CUPS logs
tail -100 /var/log/cups/error_log

# Restart CUPS
sudo systemctl restart cups

# Enable CUPS on boot
sudo systemctl enable cups

Print Queue Architecture

code

┌─────────────────────────────────────────────────────────────┐
│                    PhotoBooth Backend                        │
│                                                             │
│  ┌───────────────┐    ┌───────────────┐    ┌─────────────┐ │
│  │   PrintJob    │───>│ PrintService  │───>│   CUPS      │ │
│  │   Entity      │    │   (pycups)    │    │   Daemon    │ │
│  └───────────────┘    └───────────────┘    └─────────────┘ │
│         │                                         │         │
│         │                                         ▼         │
│         ▼                                  ┌─────────────┐  │
│  ┌───────────────┐                        │   Canon     │  │
│  │   SQLite      │                        │   Selphy    │  │
│  │   (persist)   │                        │   CP1500    │  │
│  └───────────────┘                        └─────────────┘  │
│                                                             │
└─────────────────────────────────────────────────────────────┘

Print System Skill

Quick Reference

CUPS Configuration

Installation

Printer Setup

CUPS Web Interface

Print Commands

Submit Print Job

Job Management

Printer Status

Print Job States

Error Handling

Printer State Reasons

Check Printer Errors

Python CUPS Integration

Using pycups

Using subprocess (fallback)

Troubleshooting

Printer Not Found

Jobs Stuck in Queue

Print Quality Issues

CUPS Service Issues

Print Queue Architecture

Related Documentation