| 摘要 |
PURPOSE:To diminish malfunction, by providing a means for detecting mount/ dismount of a print font cartridge and a means for disconnecting the bus of print font cartridge from the inner bus of a printer on the basis of said detection. CONSTITUTION:SW1 is a switch which is turned OFF when a font cartridge is inserted therein and turned ON when the font cartridge is removed therefrom. Normally since the font cartridge is inserted, the switch SW1 is turned OFF to turn the transistors Q2, Q1 ON so as to apply voltage from a print head drive power source 1 onto a print head drive circuit 2'. When a print head drive signal is inputted to an input terminal 3, the print head drive circuit 2' functions to drive a print head element 2, thus carrying out printing. When the font cartridge is removed, the switch SW1 is turned ON to turn the transistors Q2, Q1 OFF. Consequently, voltage from the power source 1 is interrupted and the print head drive circuit 2' does not function even if the print head drive signal is inputted to the drive signal input terminal 3. |
