| 摘要 |
<p>PURPOSE:To make the control part of a thermal printer common by providing a thermal head control circuit usable in both of parallel and serial systems in the transmission of a drive pulse to a thermal head. CONSTITUTION:A pulse generation part 2 generates four kinds of drive pulses D, a serial data latch pulse E and a serial clock F in synchronous relation to the printing cycle signal A sent from a control signal generation part 1. P/S data B is given from the control signal generation part 1 at a low level at the time of a parallel system but at a high level at the time of a serial system. The P/S data B becomes a low level in the parallel system and a drive pulse selection signal C is transmitted to the select signal input of a selector 22 as it is. Three kinds of drive pulses D-2, D-3, D-4 are transmitted to the thermal head as drive signals and the values of these corresponding drive pulse selection signals C are 2, 1, 0. That is, when the drive pulse selection signal C is 2, the drive pulse D-2 is transmitted to the thermal head and, at the times of 1 and 0, the drive signals D-3, D-4 are transmitted to the thermal head as drive signals.</p> |
