The HCC 40110B (extended temperature range) and HCF 40110B (intermediate temperature range) are monolithic integrated circuits, available in 16lead dual in-line plastic or ceramic package. The HCC/HCF 40110B is a dual-clocked up/down counter with a special preconditioning circuit that allows the counter to be clocked, via positive going inputs, up or down regardless of that state or timing (within 100 ns typ.) of the other clock line. The clock signal is fed into the control logic and Johnson counter after is preconditioned. The outputs of the Johnson counter (which include antilock gating to avoid being locked at an illegal state) are fed into a latch. This data can be fed directly to the decoder through the latch or can be strobed to hold a particular count while the Johnson counter continues to be clocked. The decoder feeds a seven-segment bipolar output driver which can source up to 25 mA to drive LEDs and other displays such as low-voltage fluorescent and incandescent lamps. A short duration negative-going pulse appears on the BORROW output when the count changes from 0 to 9 or the CARRY output when the count changes from 9 to 0. At the other times the BORROW and CARRY output are a logic 1. The CARRY and BORROW outputs can be tied directly to the clock-up and clock-down lines respectively of another HCC/HCF 40110B for easy cascading of several counters. September 1988