CIRCUIT FOR DETECTING AND ELIMINATING PIN DATA HEIGHBORING WITH OTHER PIN DATA IN DOT MATRIX PRINTER

摘要

The circuit detects and eliminates the adjacent dot data to prevent the damage of the headpin when the down-loaded data is made by mistake. The circuit includes inverters (I3-I26) for inverting the old data transmitted from latches (L4-L6) when the old data and new data shows the difference of a half period, an adjacent dot remover (6) having AND gates (AND1-AND24) for detecting and removing the dot data of the pin with frequency of T/2 by using the logical combination of the new data signal supplied from the latches and the old data signal inverted by the inverters, and an old data latch unit (5) for latching the old data and for transmitting the latched old data with one byte unit according to the output enable signal supplied from a microcomputer (1) .