Chapter 88-bit TimerVIII - 38 Event Count8.6 Event Count8.6.1 OperationEvent count operation is to count the rising edge of the TMnIO pin input as count clock.■ Event Count OperationWhen the TMnIO pin is selected to the clock source, the event counter operates. The event count operation meansthat the binary counter (TMnBC) counts down the external signal input to the TMnIO pin. The underflow inter-rupt request is generated at the binary counter underflow. The relationship between timers and event input pins isshown below.Table:8.6.1 TImer and Input Pin■ Setting the Base RegisterSet event count numbers that generate interrupts to the base register TMnBR.Interrupt generation count number = TMnBR setting + 1■ Count Timing of TMnIO pin inputTMnIO pin input is sampled by IOCLK. The rising edge of TMnIO pin input is counted, and the binary counter iscounted down. The pulse width should be IOCLK × 1.5 or more to detect the rising edge.Figure:8.6.1 Count Timing of TMnIO Pin InputTimer 0 Timer 1 Timer 2 Timer 3 Timer 4 Timer 5 Timer 6 Timer 7 Timer 14 Timer 15 Timer 16 Timer 17Pulse outputpin- TM1IOpin(P31)TM2IOpin(P32)TM3IOpin(P33)TM4IOpin(P34)TM5IOpin(P35)- TM7IOpin(P51)- - - TM17IOpin(P16)Pin input(TMnIO)TMnLDEflagTMnCNEflagBase registerBinary counterInterrupt requestflagIOCLKSamplingN NN-1 01 00NSampling Sampling
