Frequency detection (audio)

[cncmachineguy]

Here I go out on a limb that has been broken already, change the type to ASM instead of PBP. The only thig I see in your ISR using PBP is HSEROUT and TMR=0 since you removed the hser, now its only TMR=0 Now keep in mind - YOU ARE NOT SUPPOSED to do this, but for the simple setting of TMR I think you can get away with it. Add BSR=0 as your first line in the ISR. That will stop all the system variables from getting saved and restored everytime you enter the ISR. Sound familiar?

This may be enough to make it happen just as you want. The next approach I can think of is to use the comparitor as the gate for the timer, but that may be how you are doing it now

Also, does the CMP fire an int twice or 4 times per cycle? or just 1 time?