Constants

Hardware constants and platform defaults for the GoojPrt PT-210 driver.

Contents:

  • PAPER_WIDTH_PX: native print head resolution in pixels (48 mm of printable width at 203 DPI → 384 pixels).

  • BLE GATT UUIDs: primary set plus alternates used by some firmware revisions (vendor-generic 0000ff0x service family).

  • SPP_UUID: the standard Bluetooth Serial Port Profile UUID used for RFCOMM connections (Linux only; see transport/spp.py).

  • FONT_CANDIDATES: an ordered list of absolute paths to truetype/truetype-collection files used as a platform-independent fallback font for bitmap text rendering.

goojprt.constants.BLE_NOTIFY_CHAR_UUID = '49535343-1e4d-4bd9-ba61-23c647249616'

Primary notify characteristic used by the printer to report responses (model info, status flags, …).

goojprt.constants.BLE_NOTIFY_CHAR_UUID_ALT = '0000ff01-0000-1000-8000-00805f9b34fb'

Alternate notify characteristic accompanying BLE_SERVICE_UUID_ALT.

goojprt.constants.BLE_SERVICE_UUID = '49535343-fe7d-4ae5-8fa9-9fafd205e455'

Primary vendor-custom GATT service UUID used by most PT-210 firmware builds.

goojprt.constants.BLE_SERVICE_UUID_ALT = '0000ff00-0000-1000-8000-00805f9b34fb'

Alternate service UUID found on some (often older) firmware builds. Uses the generic 0000ffxx-0000-1000-8000-00805f9b34fb pattern.

goojprt.constants.BLE_WRITE_CHAR_UUID = '49535343-8841-43f4-a8d4-ecbe34729bb3'

Primary write characteristic on the vendor-custom service.

goojprt.constants.BLE_WRITE_CHAR_UUID_ALT = '0000ff02-0000-1000-8000-00805f9b34fb'

Alternate write characteristic accompanying BLE_SERVICE_UUID_ALT.

goojprt.constants.FONT_CANDIDATES = ['/System/Library/Fonts/Helvetica.ttc', '/Library/Fonts/Arial.ttf', '/System/Library/Fonts/Supplemental/Arial.ttf', '/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf', '/usr/share/fonts/truetype/liberation/LiberationSans-Regular.ttf', 'C:/Windows/Fonts/arial.ttf', 'C:/Windows/Fonts/calibri.ttf']

Absolute paths probed in order when the caller does not provide a font. The first existing file is used for bitmap text rendering.

goojprt.constants.PAPER_WIDTH_PX = 384

Print head width in pixels. PT-210 has a 48 mm printable area at 203 DPI, which equals exactly 384 pixels.

goojprt.constants.SPP_UUID = '00001101-0000-1000-8000-00805f9b34fb'

Standard Serial Port Profile UUID (Bluetooth SIG assigned number).