Without using a step sequencer?
With a step sequencer, you're usually on an instrument track, and the midi notation just triggers a preset loop in your sequencer.
So a note spanning four bars would play a loop for four bars.
With non-sequencer style drum software, the midi notation triggers individual hits.
C2 might be kick and E2-G2 might be different kinds of snares, for example.
You can manually draw these notes in, or play them in with a keyboard or midi drum kit.