| 摘要 |
PURPOSE:To make it possible to observe an original display when segment check is not required, by performing the ordinary display or the forced display of a display segment in correspondence with the presence or absence of a running data signal after a blank is displayed for a short time when a power source is turned ON. CONSTITUTION:When a power source is turned ON, the output of a timer 1 becomes L for a short time, and a blank is displayed on a display device 14. Thereafter, pulses are outputted from the timer 1. The output of an FF2 becomes H after a specified time (2sec). When no output is generated by an engine speed detecting device 5 and a speed detecting device 7 during this period, the output of an OR gate 4 become L. Then, all segment lighting signals are outputted from a memory 11 through a selecting circuit 12, and all the segments of the display device 14 are displayed for 2sec. When the engine is started and an H signal is outputted from the engine speed detecting device 5, the selecting circuit 12 is switched, and the output pulses from the speed detecting device 7 are counted by a counter 9. The counted signal is displayed on the display device 14. Therefore, the original display can be observed when segment check is not required. |
