| 摘要 |
PURPOSE:To make it possible to easily accomplish the tests under the condition having a control unit mounted in a copier by testing the abnormality in control with the use of a microcomputer which is mounted in the control unit. CONSTITUTION:The respective outputs of a control unit 1 (or at terminals R2 to Rm) are controlled to logic ''0''. Under this control condition, the light emitting diodes 81 to 8m of a display device 6 are all lit. When a switch 7 is operated from that condition to be rendered conductive and inconductive, the respective outputs (at the terminals R2 to Rm) of the control unit 1 are controlled to logic ''1''. Under this control condition, all the light emitting diodes 81 to 8m-1 are put out. By accomplishing such testing programs, if there is such a portion between the input and output terminals of the control unit 1 as has no condition varied, at least one output terminal does not take the logic ''1'' or ''0'', and this condition is displayed in the display device 6 to make it possible to judge that there is a trouble. |
