The Gateway to Computer Science Excellence
0 votes

The circuit shown in figure is using one 4-bit BCD counter and one 4-bit binary counter. The MOD value for the counter is ?

in Digital Logic by Junior (709 points)
edited by | 73 views

I think the answer is 80.

BCD counter counts from 0-9 and starts again (mod 10).

Binary counter counts from 0-15 and starts again (mod 16)

Lets assume initially Binary counter at value 0000.

BCD counter can count on clock pulses, Binary counter increments only when Q3 becomes 1 (ie 8 and 9)

See the figure , I am including, we have 8 cycles of 10 different values . Therefore answer is 80.


Answer given is 160. I also believe that the binary counter will get incremented only when Q3 is 1 i.e. either BCD counter must have 1000 or 1001 value for the working of binary counter.  As a result answer should be 80.
If the binary counter is +ve edge triggered , only 1 value of the binary counter is incremented each cycle (at 8 only).Then we have 16 cycles of 10 different values.Then the answer is 160
Okay got it. Thanks for clarification.

Please log in or register to answer this question.

Related questions

Quick search syntax
tags tag:apple
author user:martin
title title:apple
content content:apple
exclude -tag:apple
force match +apple
views views:100
score score:10
answers answers:2
is accepted isaccepted:true
is closed isclosed:true
50,666 questions
56,167 answers
93,996 users