| 摘要 |
A ratio measuring apparatus which allows continuous monitoring of two or more digital signals so as to yield an indication of the ratio of frequencies between such signals for use in process control. The apparatus includes a channel transfer circuit adapted to rotate inputs or outputs in the apparatus for logical orientation thereof. The apparatus further includes primary and secondary counters, each of which is coupled to an input signal for processing thereof. These counters operate relative to one another for logical processing of the input signals to yield ratio information. The primary counter is coupled to a data latch system, acting as a temporary memory storage for the measured ratio information. The data latch may also be coupled to a display means. The secondary counter controls latching of data from the primary counter, to form the base counts by which the ratio information is determined, and also includes a reset decoder to reset both the primary and secondary counters after information transfer from the primary counter has occurred. An orientation decoder is used to evaluate whether the measured ratio information yields a ratio which is less than one, and will generate control signals to rotate the inputs or outputs via the channel transfer circuit. The ratio measuring apparatus and processing circuitry may be provided in a hand-held unit or rack mount configuration, for use in process parameter control in a manufacturing process, or the measurement of the relative ratio between high frequency digital information signals.
|
