Re: SED1335 LCD Controller: Screen Disturbance


Richard Phillips wrote:
Hello all,

I've been using this chip (built into an LCD module) for a while and have
the LCD inverted, i.e. background "black" and characters "green".

I find that when I write info to the screen I often get very slight
disturbances (tiny horizontal lines) appearing on the screen that vanish
again almost immediately.

I have written my code so that it only updates the SED's memory inbetween
LCD screen-line writes (if I don't do this, the problem is MUCH worse!) to
minimise flicker.

Regards,
Richard.

Its caused by writing to the video ram at the same time as the
controller is reading from it. You should be able to write at the end
of the line, or at the end of the frame. Some controllers let you slow
down the clock to give you more time. You may even be able to disable
the display for a whole frame period if you need to write a lot of data.

.

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