Method and apparatus for measuring and displaying a toner tally for a printer

The apparatus (10) has a printing unit which comprises an electrical circuit for sending print data in a serial format as a first electrical signal to a print head. A second electrical signal is also transmitted to a counter having an MSB output that produces and directs a third electrical signal to a processor. The counter also has a clear MSB input that receives a fourth electrical signal output by the processor. The MSB output remains at a first logic state until counter accumulates enough count value and then it is changed to a second logic state. The processor modifies the value of a predetermined memory to output a transition in fourth electrical signal directed to clear MSB input of counter. The MSB output is thus cleared to first logic state. The counter continues to accumulate count value at its other count outputs.