Darrel's SPWM and LCDOUT

[mister_e]

Maybe just a LCD clear... or PSU noise.. who know?

LVP_NOT set to OFF.. huh... how bad things could go with it...

[Darrel Taylor]

What surprises me is that the entire line changes to a different character.

If it was a timing problem from the interrupts, I'd think it would be more Random.
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[mister_e]

Looks like the PIC itself reset here and there... i still bet on some kind of noise... or UFO interferences... stack under/overflow?

Fishing in the dark..

[DaveC3]

Don't the DEFINES have to be in CAPs?

[mister_e]

dEFINE, define or else variant will work, what's important it's on the right of it.

[Darrel Taylor]

I googled "Optrex DMC20481" and found a post on another forum suggesting that the LCD_COMMANDUS of 2000 was too low for that display. He said that 3000 worked for him.

I pulled up the datasheet, and there doesn't seem to be any mention of the actual delays required. I guess if they're that bad, I wouldn't want to publish them either.

Something to try.
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[sougata]

Hi,

I once found that my LCD was spitting garbage and sometimes went blank. On inspection with the panel itself I found it would happen when a contactor picks up. My experiments.


1. LCD changed with a different brand --> Reduced frequency of the problem but still exist
2. LCD timing --> Reduced the missing display
3. Remove shielding from the LCD mounting --> Problem almost gone

4. Software measure taken:

Use the Flag to re-initialize and clear the LCD after contactor pick up/drop.

So what I mean to say is that in my case the LCD itself was picking up noise and not stable.