Abstract: An electronic control device for industrial sewing machines, which includes a microprocessor, a programmable fixed value memory, a read/write memory, a display and an entry keyboard. In order to be able to quickly and easily change the program according to which the sewing machine operates, the non-volatile read/write memory is arranged in a cassette provided with plug connector elements. The control device is provided with a cassette receptacle which includes plug receptacle elements which are formed and arranged to correspond to the plug connector elements.