LX-D02 receipt printer

Print on an LX-D02 Bluetooth thermal receipt printer (58 mm paper, sold e.g. as Dolebo, used with the Funny Print app) from a PC, without the phone app. Receipts can be any length and stack an icon, a title, Markdown text (lists, checklists, tables…), a QR code and a picture.

The printer's Bluetooth protocol, reverse engineered from the Funny Print app, is documented in PROTOCOL.md.

For Home Assistant, see the HA-LXD02 integration, which carries a copy of this package's protocol and renderer.

Requirements

• Windows, macOS or Linux with Bluetooth LE
• Python 3.12+

Install

pip install lxd02-printer

This installs the lxd02 module (import lxd02) and the lxd02-print command. To work on the code instead, clone this repository and install it editable in a virtual environment:

python -m venv .venv

.venv\Scripts\python -m pip install -e .

On macOS/Linux use .venv/bin/python instead of .venv\Scripts\python.

The printer switches itself off after a few minutes idle, and accepts only one connection: turn it on and close the phone app (and turn off Home Assistant's Stay connected) before printing.

lxd02-print --info

Printing

lxd02-print --icon mdi:coffee --title "Coffee break" --text "Back in 15 minutes"

lxd02-print --title Shopping --file list.md

lxd02-print --qr "WIFI:T:WPA;S:Home;P:secret;;" --title "Guest Wi-Fi"

lxd02-print --image photo.jpg --energy 5

lxd02-print --feed 20

python -m lxd02 works the same as lxd02-print.

After every job the printer advances about 10 mm of paper by itself, so the last printed line clears the tear bar. Feeds count it: --feed 12 gives 12 mm, and 10 mm is the shortest feed. The first 10–20 mm of a print can come out faint while the print head warms up.

Markdown: lists, checklists, tables

The text is Markdown, so shopping lists, to-dos and notes print formatted:

# Weekend
## Groceries
- [ ] Milk
- [x] Bread
- [ ] Coffee, **dark roast**

## Hardware store
1. Screws *(4 mm)*
2. Wood glue
   - the ~~cheap~~ good one

> Remember the bags!

| Item   | Qty | Price |
|:-------|:---:|------:|
| Apples |  6  |  2.40 |

---
```
Total   6.38
```

Unlike standard Markdown, every line break is kept. Text uses the bundled DejaVu fonts, so every machine prints identically.

Using it from Python

import asyncio
from lxd02 import LXD02, render_receipt

async def main():
    img = render_receipt(title="Shopping", text="- [ ] Milk\n- [ ] Bread", icon="mdi:cart")
    async with LXD02() as printer:  # scans for the printer; or LXD02("C0:00:00:00:00:48")
        status = await printer.wait_status()
        print(status.battery, status.no_paper)
        await printer.print_image(img, energy=3)
        await printer.feed(20)

asyncio.run(main())

lxd02.protocol.LXD02 is the protocol on its own: give it any connected bleak client (Home Assistant's, for example).

Development

src/lxd02/protocol.py, receipt.py, markdown.py and assets/ are copied unchanged into the HA-LXD02 integration. Change them here, then copy them there; HA-LXD02's tests check the copies match when both projects sit side by side.

The tests cover the protocol against a simulated printer (handshake, hold/resend, out of paper, the automatic feed), the Markdown renderer and the CLI:

pip install -e . pytest pytest-asyncio

pytest

Releasing

Releases go to PyPI through the Publish workflow, with trusted publishing (no API tokens):

1. Bump version in pyproject.toml and push.
2. Optional: Actions → Publish → Run workflow uploads that build to TestPyPI; try it with pip install -i https://test.pypi.org/simple/ --extra-index-url https://pypi.org/simple/ lxd02-printer. TestPyPI refuses a version it already has, so bump again to re-test.
3. Publish a GitHub release with the tag v + the version (e.g. v0.1.1). The workflow checks the tag matches, builds, smoke-tests the wheel and uploads it to PyPI.

Files