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7-Segment latch?
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7-Segment latch?

by Star87 on Thu Feb 26, 2009 8:43 am

Hi, was wondering if anyone could help? i've built this circuit (to a given spec) and need to build a latch in to freeze the display? im somewhat stumped... can anyone help?

Image

many thanks,
Charmaine
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Star87
 
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Re: 7-Segment latch?

by westfw on Thu Feb 26, 2009 11:31 am

The easiest thing is to put a gate in the clock line to the counter (NAND or NOR gate) and use that to just stop the counter from counting when you want the display to stop. (ie the counter HAS all the latches you need; adding an additional latch is "expensive" and probably not necessary.) A lot of counters have the gate on the clock built into them, but not the 7493...
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Please be positive and constructive with your questions and comments.