I have never liked to either play or watch any sports. A few years ago, there was a golf outing at work when I have ever tried golf for the first time. Golfing became one of my favorite things to do since. Well, I’m still playing over 100 and my non-athletic body does not cooperate very well. But I have no plan to take any class or get a coach for better play. I just enjoy to think about how to improve my swing, angle, balance, and steadiness. I have no intention or any possibility to become a professional golfer. All I want is to go out on a nice and sunny day with my wife and enjoy the time.
So, as you can imagine, I often forget how many shots I played during the game. If you are really good and can play no more than bogey, you may be easy to count how many shots you played. But that’s not the case for me. Many times, I asked myself, “was that the third or fourth?”
I have searched for golf shot counter, and for sure, found a lot of different type of counters, from beads on a string, plastic dial, to a fancy digital one with LCD displays. But none of them attracts me and thought I would design one with simple portable electronics.
At first, I thought about using one of those ATtiny chips with a small LCD. But all I need is a button switch to add 1 to the total number and show the number when I want to see it. So the ATtiny chip with the LCD sounded like overkill. And then I thought about binary display with a few LEDs. If I have 4 LEDs, it can show up to 15 which is more than I need (I’m not THAT bad). 3 LEDs might be too small because it can count only up to 7. Considering when I play triple bogey or worse for par 5 hole, I will need at least 8 or more. So, 4 LEDs it is.
Now, how to make a binary counting circuit was the question. I immediately thought about a flip-flop circuit which is a basic calculator and memory element. If I have 4 of those and connect the output to the next one, that can make a binary counter. Wait a minute… there is a binary counter chips already. I don’t need to make one myself. So I ordered a part from Digi-key and that part is SN74HC393. This one has dual 4 digit binary counters, but I would use only one of them.
As soon as I got the part, I connected switches and LEDs and checked if it works fine and found I need a debouncer for the SHOT button switch. That was fixed easily with a Schmitt trigger with a resistor and a capacitor.
Below schematic is the final circuit diagram.
I ordered the PCB and will post the result as soon as it’s ready to show.