A 2.5 GHz frequency counter
An AVR controller can be used as a counter, although it is a bit more involved than with a PIC. The reason is that a PIC (at least the 16F84) has an asynchronous counter input. This input will handle frequencies up to app. 40 MHz. AVR’s have a synchronous counter input which is sampled with the clock frequency, so it cannot measure frequencies over half the clock frequency. So, when using a 4 MHz clock, input frequencies must be lower than 2 MHz. Use 40% of the clock frequency to be on the safe side.
| A 2.5 GHz frequency counter Check out A 2.5 GHz frequency counter website www.qsl.net |
||
