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Thread Starter

wjunfa

Joined Jan 23, 2009
3
thanks for the help, it works great by connecting an invertor at the end

How do i add-on the start/stop and preset inputs such that at any time, the counting could be paused or resumed using the switch or preset to 11111 ?
 

Wendy

Joined Mar 24, 2008
23,415
Preset in this case is reset. A simple external AND gate will provide the start/stop functions, since that function is only on the 7490.
 

Thread Starter

wjunfa

Joined Jan 23, 2009
3
Could you show me how to connect up using the AND gates as start/stop?
Dont you need a 7474 flip-flop to do it?
 
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