In the AB PLC's, including SLC's, Micrologix, CompactLogix, FlexLogix, ControlLogix, and PLC5's, ALL data is by default retentive. You don't need to latch them, just setting bits in the data tables (classic) or tag browser (Logix), they will hold the state as long as the backup battery holds.
Note that you can also set things offline, and they will be downloaded.
As mentioned above though, anything driven with an OTE instruction is auto-cleared on the first-scan when going into run.