The Intersil HCTS190MS is an asynchronously presettable BCD Decade synchronous counter. Presetting the counter to the number on the preset data inputs (P0 - P3) is accomplished by a low on the parallel load input (PL). Counting occurs when (PL) is high, Count Enable (CE) is low and the Up/Down (U/D) input is either low for up-counting or high for down-counting. The counter is incremented or decremented synchronously with the low-to-high transition of the clock.