The 'F192 is an up/down BCD decade (8421) counter. Separate Count Up and Count Down Clocks are used, and in either counting mode the circuits operate synchronously. The outputs change state synchronously with the LOW-to-HIGH transitions on the clock inputs. Separate Terminal Count Up and Terminal Count Down outputs are used as the clocks for a subsequent stage without extra logic, thus simplifying multistage counter designs. Indi-vidual preset inputs allow the circuit to be used as a programmable counter. Both the Parallel Load (PL) and the Master Reset (MR) inputs asynchronously override the clocks.