Trying to figure out how to design this with decent precision but having trouble getting this started. I've worked with 555's before but not for precise counting that can be modified in steps.
I'm trying to come up with a 5 volt system that accurately pulses an output of +5v that is measured and displayed in pulses per minute, or beats per minute, between 60 and 240. The BPM should be adjustable by 2 momentary buttons which will step the timer +1 and -1. It would also be great if there could also be a second set of buttons for +10 and -10 steps.
Is using a 555 timer the wrong way about this? Is there something more precise I can use to reference the gating? Is there already an IC out there that can do this on its own and do a compare to calculate the maths?
Apologies for not posting what I have so far. I'm on version 80-something on my breadboard and nothing has been working accurately so far. I also want to stay away from having to program roms and stick with discrete IC's. Again, I DO NOT want to be programming chips.
I think what I'm after might be a function generator with a frequency counter, but I don't know if that's the best way to go.