Terminology

As this software grew more and more powerful, it became important to make some terms clear and use them consistently. Here’s a list of terms frequently used in the context of brother_ql and what they signify:

  • model - The printer model of Brother’s QL-Series label printers. In this software package, each supported model has a model identifier (eg. QL-500 or QL-710W) used to specify the model on the command line or in function calls.
  • printer - A printer (identifier) is a string determining the printer to be used in the context of this package (eg. tpc://192.158.0.20:9100, file:///dev/usb/lp0 or usb://0x1234:0xABCD). If the prefix specifying the backend (like tcp:// or usb://) is given, there is no need to set the backend separately.
  • backend - The backend used to establish communication with the printer (eg. pyusb, linux_kernel or network).
  • label - The kind of label to be printed on. Each label has a label identifier string to specify the label on the command line or in function calls (eg. 62 standing for endless 62-mm tape or 17x54 for 17mm x 54mm die-cut labels). The label types have form factors such as ENDLESS, DIE_CUT or ROUND_DIE_CUT.

Additionally, a couple of further terms are commonly used within this software relevant for developers (and thus less important for end users):

  • opcode - An operation code code for the printer as defined by Brother’s raster language. It’s the first syllable of an instruction.
  • instructions - A set of binary code containing raster opcodes and (optionally) payload data. Those instructions describe the printer setup together with the image to be printed. They can be stored in a binary file or directly be sent to a label printer.