> From:         Andre Miller[SMTP:andre.miller@BLUERIVER.CO.ZA]
> Sent:         Wednesday, March 17, 2004 5:51 AM
> To:   PICLIST@MITVMA.MIT.EDU
> Subject:      Re: [PIC:] Multiplexing seven segment displays, correct resistor values?

> Hi,

> If I increase the 'on' time for a display, wont this then also increase the
> 'off' time for the other displays, thereby negating the benefit? I should be
> able to get this same effect by increasing the prescaler on my timer
> interrupt that drives the displays. I tried changing this and the lower
> frequency of updating didn't seem to make a difference, except that it
> starts to flicker noticibly when its too low :-).

>  _____
>
> Andre Miller

The duty cycle for each display is 1/4, and this is the only part of
the switching which affects brightness. Changing the frequency
while keeping the duty cycle at 1/4 will only change the overall
appearance of flickering. The only other factor controlling brightness
is the current per segment.

John Power

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