0 votes 0 votes Pr0,Pr1,Pr2???? Digital Logic ripple-counter-operation + – hs_yadav asked Nov 30, 2017 hs_yadav 862 views answer comment Share Follow See all 2 Comments See all 2 2 Comments reply joshi_nitish commented Nov 30, 2017 reply Follow Share Pr stands for active high preset, this means whenever Pr=1, then it will set the flipflop's output Q=1. PS: Pr do just opposite work of reset. 0 votes 0 votes stanchion commented Dec 5, 2017 reply Follow Share I quess, this circuit is acting as MOD 7 counter as counting sequence is 0->1->2->3->4->5->7-> 0 .... SINCE pr means preset ,here preset is active low preset due to that bubble ie. when i/p to pr1=0 then pr will set Q1=1, So when counter is at stage 5 (101), next stage is count 7(111) as Q2=Q0 =1 as i/p to nand gate o/p = 0 which triggers pr =1 0 votes 0 votes Please log in or register to add a comment.