[amibroker] Previous/last occurrence

[bernardedmond01]

Hi
If I were buying on an upward cross of RSI(15) but I wanted to use as a 
reference point the previous cross, how would I refer to this previous 
cross? I don't want to use the "Barssince" function because there could 
be either zero or multiple crosses in my chosen timeframe - I just 
simply want to know when the last one occurred.
Thanks