Building a Counter for HeartBeat

[tenacity2986]

I have limited hardware components I can use for this obstacle. Let's say I have precision rectified the input heartbeat signal into a square wave... I am trying to count the number of squarewaves/heartbeats and display them on two 7-segment displays refreshing every 15 seconds...
I can only use a 4029 Up.dwn counter and a BCD driver to 7 segment display...
My issue is that the 4029 is going to need to refresh every 15 seconds however ! the output needs to be in bpm (Beats per minute) which means it is off by a factor of 4... How can i multiply the output by 4 or is there a clever way i can do this with the timer that resets the 4029 every 15 seconds? PLEASE HELP. I've looked everywhere. even minute insight may prove valuable. thanks in advance.

 

[Danger]

Hey, Tenacity.
I can't help you at all; I know nothing about electronics. It does strike me, however, that this might get better participation if you have it moved to Electrical Engineering or maybe even the Computer section.

 

[Bob S]

How about a counter that updates every second. Put your heartbeat pulse into a 64 bit shift register that shifts every 0.234 second, and you have a up-down counter that keeps track of all the "1" bits in the SR during a continously updating 15 second interval.

 

[tenacity2986]

huh , interesting thought, but I am not sure i can use a shift register... these are the components i can use...
4011 CMOS NAND (2 input)
4029 CMOS UP/DN COUNTER
4043 RS TYPE FF
4093 SCHMITT TR NAND
4511 LED DRIVER
7 SEGMENT DISPLAY
7400 NAND (2 Input)
7402 NOR (2 Input)
7404 INVERTER
7408 AND
7410 NAND (3 Input)
7420 NAND (4 Input)
7430 NAND (8 Input)
7432 OR (2 Input)
7437 NAND (High current)
7440 NAND (High current)
7442 BCD TO 1 OF 10 DECODER
7474 D TYPE FF
7476 JK TYPE FF
7486 EXOR
7490 DECADE COUNTER
74151 DATA SELECTOR
74153 DATA SELECTOR
324 OP-AMP
339 OP-AMP
356 OP-AMP
741 OP-AMP
386 AUDIO POWER AMPLIFIER
555 TIMER
RED LEDs
SK3024 PNP BJT
ZENER DIODE (5V)
IN914 DIODE

Im using the 4029 CMOS UP/DN COUNTER with the LED driver that outputs to the LED. any ideas using these components?