Cat Printer

"cat printer 🥺"

A central repository to link to documentation and projects related to cat-shaped bluetooth thermal printers. PRs encouraged.

Protocol implementations

In chronological order:

| Name | Comments | Bluetooth Library | Platforms verified working | |---------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------|-------------------|----------------------------| | WerWolv / PythonCatPrinter | WerWolv's original implementation bassed on their blog post | Bleak (Python) | | | amber-sixel / PythonCatPrinter | AmberSixel's fork of WerWolv's implementation. | Bleak (Python) | | | the6p4c / catteprinter | the6p4c's Rust library | btleplug (Rust) | Windows¹ | | JJJollyjim / PyCatte | A barebones Python implementation | Bleak (Python) | Linux | | xssfox / print_server.py | Featureful Python implementation with an HTTP API, text rendering, and PostScript printing. | Bleak (Python) | Linux |

¹: Appears to be broken on Linux due to an issue where btleplug never correctly recieves the dbus property-change message which notifies it that a connection has been established, even though "Connected" and "Services Resolved" are displayed in bluetoothctl. I'm guessing this is a locking issue involving the CondVar, or something like that?

Protocol docs

WerWolv's blog post contains initial docs from RE of the Android app, however more is now known.

TODO: consolidate what is now known.

Hardware

Four different model names (included in bluetooth advertisements) have been observed:

GB01

Known owners

• WerWolv (blue)
• Iris (blue)

Internal photos

See WerWolv's blog post.

Notable components

• JL MCU with built-in Bluetooth (model number not clearly readable)

GB02

Known owners

• the6p4c (pink)

Internal photos

| Front (assembled) | Back | |---|---| | | |

Notable components

• JL MCU with built-in Bluetooth (model number not clearly readable)

GT01

Known owners

• JJJollyjim (pink)
• xssfox (pink)

Internal photos

| Front (assembled) | Back | JL Chip (closeup) | |---|---|---| | | | |

Notable components

• JL MCU with built-in Bluetooth. Markings: JL BP02989-56C4

USB Behaviour

Does not enumerate. Data lines are routed, however. perhaps it's used for programming, as described here?

YHK-C200

Known owners

• Stary2001 (blue)

Internal photos

| Front (assembled) | Back | Back (closeup) | |--------------------------|--------------------------|--------------------------| | | | |

Notable components

• GD32F303 (STM32 clone)
• BARROT bluetooth module
• Fentech SPI Flash
• Unpopulated UART header

USB Behaviour

Enumerates as an HID device!

[15361.648980] usb 7-3: Product: Print-M200
[15361.648981] usb 7-3: Manufacturer: Pintron-M200
[15361.648982] usb 7-3: SerialNumber: pintronhid0000001