The MC54/74F168 and MC54/74F169 are fully synchronous 4-stage up/ down counters. The F168 is a BCD decade counter; the F169 is a modulo-16 binary counter. Both feature a preset capability for programmable operation, carry lookahead for easy cascading, and a U/D input to control the direction of counting. All state changes, whether in counting or parallel loading, are initiated by the LOW-to-HIGH transition of the clock. Asynchronous Counting and Loading Built-In Lookahead Carry Capability Presettable for Programmable Operation