Control system for positioning a marker on a cathode-ray tube display

摘要

A control system for positioning a marker on a cathode-ray tube display (18) includes position registers (16) operable to store the position of the marker on the screen. Input means (11) generate signals which represent desired changes in the position of the marker. Comparison means (15) response to these signals to produce an output pulse corresponding to each increment of change in the position of the marker. Control means (14) control the operation of the comparison means. Frequency-sensitive means (17) are provided to control the rate at which pulses are applied to the position registers (16).