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kicad sn74lv8154 Sep 5, 2016
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README.md

PROJECT HOMEPAGE

sn74lv8154 AVR counter

The sn74lv8154 is a dual 16-bit counter than can be configured to act as a 32-bit counter. Although the datasheet doesn't report functionality at VHF frequencies, in my tests it works at least at 100MHz. The way I operate it is as a frequency counter with a gate. I'm measuring unknown frequencies with 1 pulse per second gate (from a GPS unit).

This program measures frequency with the AVR and outputs frequency (counts) to a computer via the serial port. Included is a barebones python script to display these frequency counts.

note: My tests on a breadboard showed this setup easily counts VHF frequencies over 100MHz (screenshot below). However, when I built it in an enclosure, it struggled to measure frequencies above 70MHz. It works well at 50MHz. I suspect this is because the signal I'm using doesn't travel well through 50 Ohm coax, but nontheless note that this is somewhat sketchy at VHF frequencies. Here it is clocking a canned 50MHz oscillator.