The AN2573 is an industrial grade, user programmable digital rate indicator capable of measuring RPM, inches per sec., liters per min., cycles per sec., feet per sec., bottles per min., and more. Due to the unique “Digitally Programmable Charge Pump Technique” the instrument accommodates virtually any transducer input signal from pulse inputs such as cam-driven microswitches or photo cells, to sinewave inputs from tachometers, flow meters and many other rate transducers. Concealed, yet front panel accessible microswitches provide all programming without special tools or operator training. Versatility is further enhanced by the programmable pulse output, which is ideal for totalizers and counters and by the analog output, which can be used for remote readout or strip chart recorders. In addition, a full complement of digital interface lines from latched and buffered parallel BCD to status, control and “ handshaking” signals are provided—for processor, printer or comparator interfacing.