invert signal on active low interrupt

Im aware that this might sound stupid and trivial but is possible and how to use this signal


to make this one


using only logic, not microcontroller

found it, T flip flop is the answer, T High, and source signal to clock

[u]T flip-flop[/u][edit]

A circuit symbol for a T-type flip-flop If the T input is high, the T flip-flop changes state ("[u]toggles[/u]") whenever the clock input is strobed. If the T input is low, the flip-flop holds the previous value. This behavior is described by the characteristic equation: Q_{next} = T \oplus Q = T\overline{Q} + \overline{T}Q (expanding the XOR operator) and can be described in a truth table:

"T" stands for TOGGLE. (hence the name, duh)

BTW, not that it matters any more but your post title doesn't match your problem. You were looking for a frequency divider , which is quite different from simple inversion, as suggested by your post title. I'm just sayin'.....

Now when I look at it it is a divider, but initially problem was in managing alarm interrupt signals for standalone use of RTC, and since periods are long and its asynchronous I wasn't looking at it that way

You'd normally toggle with a DQ flipflop that has a Qbar output. Qbar->D, input -> clk