Wire Protocols

This driver implements three distinct wire protocols across the LabelWriter line. The device's engine.protocol field selects which one applies.

lw-raster — LabelWriter 300 / 400 / 450 / 4XL

The classic LabelWriter chassis (300-series through 450-series, plus SE450 / Wireless / Turbo / Twin Turbo / 4XL). 672-dot or 1248-dot heads, 1-byte status reply, raster rows framed with SYN (0x16) or RLE-compressed (0x17). See LW raster.

lw5-raster — LabelWriter 550 / 550 Turbo / 5XL

The next-generation chassis. Different job structure entirely — explicit job header (ESC s), per-label ESC D 12-byte preamble, mandatory job trailer (ESC Q). 32-byte status reply with NFC-derived media diagnostics (SKU number, label count remaining, counterfeit detection). Genuine DYMO consumables are enforced in firmware. See LW5 raster.

d1-tape — LabelWriter Duo tape engine

The Duo's tape-side engine speaks the standard D1 protocol — same encoder, same 1-byte status, same opcode vocabulary as a standalone LabelManager (the Duo is electrically a LabelManager + LabelWriter sharing one cable). Documented separately in @thermal-label/d1-core.

The label side of the same chassis lives on a different USB interface and speaks lw-raster.

When to use which encoder

The driver dispatches automatically:

encodeLabel(device, bitmap, options, media);
// engine.protocol === 'lw-raster'  → 450 byte stream
// engine.protocol === 'lw5-raster' → 550 byte stream
// engine.protocol === 'd1-tape' → d1-core's buildPrinterStream

The encoder source:

File	Covers
protocol.ts	lw-raster encoder + the unified dispatcher
protocol-550.ts	lw5-raster encoder, SKU / engine-version parsers
status.ts	1-byte (450) / 32-byte (550) status parsers
@thermal-label/d1-core	d1-tape encoder + 1-byte status parser