| 摘要 |
PURPOSE:To execute a setting operation of exposure infomation easily, quickly and exactly, by detecting a switch operating time, and controlling 1 step and continuous updating of a digital signal. CONSTITUTION:When an operating switch SW2 is turned on, a resetting signal of a counter 21 of a clock input controller is inverted to ''0'', the counter 21 is not reset, and the counter 21 generates a detecting pulse of time width corresponding to the operating time of the switch SW2 from a terminal Q4, and controls an AND gate 22 where a frequency- dividing output from a frequency- dividing circuit 23 passes through. As a result, set contents of an up-down counter 2 which makes the frequency-dividing output a clock, counts it and sets a digital exposure information are updated continuously. On the other hand, when the switch SW2 is operated for a short time, the contents of the counter 2 are updated by 1 step, and a setting operation of exposure information can be executed easily, exactly and quickly. |
