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7 seg display multiplexing frequency

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Jack// ani

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Hi all,

Although I've not tried yet....should I multiplex two 7 seg display at 32mSec ??

Thanks
 

rkodaira

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Hi !

It is too low, probably they will blink. I used to multiplex led display with 40Hz or higher frequency. For two displays, something around 10ms on and 10 ms off (50Hz) will work.
 

7rots51

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I recommend you to use 100HZ (many monitors nowadays use 85HZ or higher),at this frequency you have no flickers.
 

echo47

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I usually scan LED displays at several hundred Hertz. I find 100 Hz distracting, because I see the flicker when I slightly move the LED or my eyes, especially if the LED is located in my eye's peripheral field.
 

Jack// ani

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Thanks all....that was what I suspected!! Actually I'm using timer0 overflow interrupt at 32mSec for multiplexing and for other purpose as well!! If I lower down its time period other....timing factor will get disturbed, so how to cope up with this trouble. BTW, I'm using 90S2313.
 

metal

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Hi

Although I don't know much about Atmel, but you may want to poll the timer rather than using its interrupt, you can test the vlaue of the timer to see whether it has passed a predefined number, if so, go to display routine.
 

pvinbox@yahoo.com

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hai

less than 10ms is nice
otherwise it will blink
reduce the time when number of displays
will be more
10ms is enough for 5 displays
 

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