A driving device of a printer head which receives serial print data of the maximum n bits tone, and selects a conductive waveform of a head by this print data for printing, comprising a serial parallel conversion circuit which converts serial print data of two bits tone for example into parallel data and which can convert maximum four bits in parallel, four bit parallel shift register for transferring the parallel print data converted by this conversion circuit two bits by two bits, and a mask circuit for masking the four bits parallel data transferred from this shift register other than a necessary two bits, and a conductive waveform of a head is selected by the two bits print data from this mask circuit to print. |