Bar-Graph Counter

Status
Not open for further replies.
Hi,
I need to make a 0-99 event bar-graph counter. I have tried to use two cascaded 4017 decade counters but I can't get them to behave properly. The first one counts 0-9 then it has a carry-out to the second to count ten, twenty, thirty, etc. The problem I keep getting is the second counter always has the tens LED on when I power up, then when the count on the first reaches 10, it increments the second counter to twenty. How can I inhibit the second counter until the tenth count? Any thoughts? Thanks.
 

Attachments

  • 0-99_event_counter.jpg
    60.1 KB · Views: 694
I didn't try to analyze your problem, but I found the schematic below in the TI CD4017 datasheet.
 

Attachments

  • Cascading_CD4017s.gif
    9.9 KB · Views: 523
A power on reset R-C would stop the tens output from starting from 10, but since the 4017 clocks on the rising edge, the tens counter will light at the 5 count unless you use the circuit Ron showed.
 
Status
Not open for further replies.
Cookies are required to use this site. You must accept them to continue using the site. Learn more…