SN74ALS569AN

The SN74ALS568A decade counter and
?ALS569A binary counters are programmable,
count up or down, and offer both synchronous and
asynchronous clearing. All synchronous functions
are executed on the positive-going edge of the
clock (CLK) input.
The clear function is initiated by applying a low
level to either asynchronous clear (ACLR) or
synchronous clear (SCLR). Asynchronous (direct)
clearing overrides all other functions of the device,
while synchronous clearing overrides only the
other synchronous functions. Data is loaded from
the A, B, C, and D inputs by holding load (LOAD)
low during a positive-going clock transition. The
counting function is enabled only when enable P
(ENP) and enable T (ENT) are low and ACLR,
SCLR, and LOAD are high. The up/down (U/D)
input controls the direction of the count. These
counters count up when U/D is high and count
down when U/D is low.