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Peg plans for a dobby

A tie-up is a grid on screen; a dobby wants it as a lift table in a precise column order. This is how Draft turns one into the other and the settings that make it match your interface.

From tie-up to lift table

The tie-up says which shafts each treadle raises. On a treadle loom you press the treadles in the treadling order; on a dobby there are no treadles, so the treadling and the tie-up collapse into one lift table - one row per pick, a mark for every shaft that rises on it. Draft writes that table as the peg plan, in the shaft order your interface expects, counted from the front or the back as you set under Preferences.

Column order and the end marker

Mechanical and electronic dobbies disagree about which column is shaft one and whether a raised shaft is a one or a hole. The export dialogue prints the convention in its preview header so you can check before you commit a warp to it. Several interfaces also expect a trailing blank pick as an end marker; Draft writes one, a detail that went missing in 3.4.0 and came back in 3.4.2, listed on the changelog.

Over a serial line

For a dobby driven over RS-232, Draft sends the same plan at 9600 or 19200 baud with the stop bits the interface wants; the formats page lists the serial settings and every file the program reads and writes. A structure to practise on is any entry in the catalogue - its tie-up is the lift table in miniature.