the project board enables the measurement of frequencies in the range 0Hz to 50MHz. The reading is displayed on four 7 segment LED displays, and shown in engineering format x.yz En, eg. 5.756 means 5.75*10^6. The 4 displays are controlled by the microprocessor outputs using time division multiplexing. The input frequency is "gated" for a precise duration of time, the gate is implemented in software as an accurate delay. If the frequency is below 128Hz the digits blink to warn that the error may be greater than the device resolution.
The P07 Meter is only suitable for low voltage (24V max.) frequency measurement. 6V grounded power supply is required