Method of producing stitch patterns in an electronic sewing machine

A method of producing stitch data from which different complete patterns may be sewn by an electronic sewing machine, the method being designed to avoid wasted space in a read-only memory contained within the sewing machine by avoiding repetitious storage of stitch data therein, comprising the steps of:

• dividing each of the different complete patterns to be sewn into individual unit patterns, which can be selectively combined to form at least one complete pattern;
• storing stitch data characteristic of the unit patterns in a read-only memory;
• selecting one of the complete patterns to be sewn by actuating a pattern selecting switch;
• ascertaining via a central processing unit which unit patterns are required for sewing the selected complete pattern;
• ascertaining via the central processing unit an order in which such required unit patterns should be executed in sewing the selected complete pattern;
• using the central processing unit to read stitch data characteristic of such required unit patterns into a random-access memory in said order;
• and
• using the central processing unit to read stitch data out of the random-access memory in said order.