We are using a PCI 6624 counter/timer to find the position of a cam tooth with respect to the crank position of an engine. We have 2 cams and the reference is a 60-1 teeth crank wheel (60 teeth with 1 missing...which means each tooth is 360/60=6 degrees). The 1 missing tooth is to reset the counter to 0 and count again to 60 (or 0 degrees and upto 360 degrees). We use 3 channels, 1 carries the crank(reference), and the other 2 channels carry 2 cam signals( one pulse for every 360 degrees but position might vary).
All the 3 clocks have to be started at the same time for position synchronization. If we can run a loop which will execute only when the crank pulse goes high or low (like a frequency in trigger) then this would be easy but we are able to run the loop only periodically like 30ms or so, which means we can never count all the teeth on the crank and the cam position in terms of crank angles cannot be obtained from this. But we know the hardware is capable of recording all the pulse (in a buffer and output the latest one) since we operate only in kHz. Please advice. A sample program would really help.
