| 摘要 |
PURPOSE:To display the accurate time passed of a tape, by measuring the revolving cycles of a feed reel and a take-up reel respectively then calculating and displaying the total sum of the time required for a revolution of the take-up reel. CONSTITUTION:Clocks TR.CLK and SR.CLK of the pulse train obtained by a photocoupler, for example, which are fed from a take-up reel TR and a feed reel SR are amplified AT and AS and fed to a CPU. These clocks are set by enable signals EST and ESS given from the CPU, and the time signals sent from an oscillator are counted by counters CNTT and CNTS. A cycle measuring circuit PCM measures the revolving cycles of both reels SR and TR for every revolution of the reel TR. The CPU calculates the time required for each revolution of the reel TR and displays it to a display DP. In such a way, the time passed of a tape is accurately displayed regardless of the type and the thickness of the tape. |
