Abstract: A crosspoint encoder having a n-key rollover data collection system in which all keystrokes are recognized. A phantom key detection routine detects phantom key conditions and provides for temporary storage of subsequent keystrokes until the phantom condition is removed thus ensuring uninterrupted recordation of all keystrokes.

Abstract: A print wheel mounting means. The print wheel has pivot posts formed integrally thereon. The pivot posts are spring-locked into channels in a connector attached to the print wheel drive shaft. The connector thus positions the print wheel to be pivoted onto the print wheel drive shaft.

Abstract: A power amplifier is disclosed for controlling the current flow through a load. The power amplifier includes a plurality of switching elements connected in bridge fashion with the load and a first predetermined power source for coupling the load across alternate output terminals of the power source in accordance with the levels of a plurality of control signals respectively applied to the plurality of switching elements. Circuitry is coupled to a second predetermined power source for generating the control signals. Logic circuitry, when enabled, is capable of coupling each of the control signals to the respective switching element. A power monitor circuit compares the voltage level of the second power source with a predetermined reference potential and generates a current disable signal when the voltage level is less than the reference potential.