Original Publication Date: 1987-Jan-01
Included in the Prior Art Database: 2005-Jan-31
Counting logic is disclosed which eliminates counting errors usually associated with direction-of-motion changes that occur very close to a count decode time. A bidirectional encoder is used to track the position of a movable element. The encoder's two 90Œ shifted output signals are decoded to provide position information. These two signals are processed by a logic network, and the output of this network drives an up/down counter. At any given time, the count within the counter is an indication of the position of the movable element. The two encoder signals 10 and 11 are applied to 7474-type flip- flops 12 and 13, respectively. These two flip-flops are connected to similar-type flip-flops 14 and 15.