What voltage are you supplying the 4000 series cmos logic on?
Are you mixing TTL/CMOS?
What is the amplitude of the BPM clock?
Are you sure that it is a "clean" square wave? (
Did you put any 100nF bypass caps from Vdd to Vss on the logic chips?
Hook your Green LED to a 5V supply through a 1K resistor. How bright is it? You can NEVER run an LED without a current limiting resistor in series with it. I suggest getting an ultra-bright LED. Even when running it at 4mA, it will be bright enough. I have some first generation green LEDs that are really dim even with 20mA flowing through them.
ok some of those questions i don't understand.
all three of the chips are connected to a regulated 5v supply from the device putting out the clock signal
i am not sure what you mean by TTL/CMOS but the chips are HCF4024BE, CD4012CN and CD4011BE
i am pretty sure the clock is 0v to 5v
the clock may not be a 100% perfect square wave but from what i can find out it seems to be perfect.
there is no bypass cap fitted, so i have just fitted one but no difference
i hooked up a high brightness white LED, this is very bright when connected to 5v with the 1k resistor, but it is very dim when connected to the output of the ripple counter, still it is brighter than the green one which makes it easier to see, and when trying to count it (i set the BPM to 60) it seems to be flashing roughly 10 a second, so ten times faster.
but the reset part seems to work, and it is doing something, but i am not sure why it is counting so fast unless it is a problem with my clock signal.
i used a microprocessor to do the same job, and that is working fine, so i know the clock is working, and i know its 24 pulses that need to be counted, i wonder if the ripple counter is maybe more sensitive than the microprocessor.