# Detecting level in a Pulse Train

Assume I have a square wave pulse train, where each high lasts for H and each low lasts for L seconds. I sample this waveform and have the sequence of numbers.

Question is what should be the sampling rate if I just want to know what level I am in(High or Low)?

I know by Nyquist I can find the sampling rate for full-reconstruction of the pulse train, but I don't need the full reconstruction. I just want to be able to:

1. Don't miss any High or Low

2. Detect all Lows and Highs

So, $T_s < \rm{min}(L,H)$.