Abstract: A signal consisting of a sequence of contiguous line segments is generated to simulate a function. First programmable inputs define a first parameter (duration) corresponding to each of the line segments. Control signals are generated which are representative of each of the first parameters. A reference voltage representative of a second parameter (end point) corresponding to each of the line segments is generated and stored. The output signal comprises a portion representative of each of the line segments. Each portion is generated over a period determined by the control signal corresponding to the line segment which the portion represents, has an initial value determined by the stored reference voltage corresponding to the previous line segment, and a final value determined by the reference voltage corresponding to the line segment which the portion represents.