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Is the I2C/serial LCD220 damaged?

Started by naimead June 26, 2005
Hi guys,

I am trying to display a message in my LCD by using basicX.I am using
exactly the same connections as before and exactly the same code.The
main problem is that nothing is being displayed in the LCD anymore.I
don't think this is a basicX problem since it downloads the code
fine.Any ideas about the problem?


Well, there are sure a lot of possibilities. A wire knocked loose?

I had a parallel LCD connected via ribbon cable and a DB-25.

Well, after I was messing with it, it stopped working after several
years of flawless service.

I thought I blew the LCD's brains somehow (static electricity). Then
I realized I could just barely see ghostly letters on the display. It
was the ground wire! Better ground and it worked fine.

-Tony

-- In basicx@basi..., "naimead" <naimead@y...> wrote:
> Hi guys,
>
> I am trying to display a message in my LCD by using basicX.I am
using
> exactly the same connections as before and exactly the same code.The
> main problem is that nothing is being displayed in the LCD anymore.I
> don't think this is a basicX problem since it downloads the code
> fine.Any ideas about the problem?


Tony,my problem with this LCD is that although i do see black boxes
the screen i don't see any data that make sense as before!!!Of course i
tried to use the contrast but the only thing i managed to do is to see
the same black boxes not as faint as before.Is it possible to be basicX
problem?I checked the connections i had hard wired on the pins but
they seem fine!


Well, if you get the black boxes, then at least some of the LCD
circuitry is working. It does not prove it is entirely functional,
but it is suggestive.

At this point the only way to be sure is to substitute "known good"
parts. If you had an oscilloscope (I don't!), then you could read
the signals. Otherwise you have to guess.

I have no other suggestions. It seems that we reached an impasse.
The code is the same as before, so we think it is "known-good", the
BX seems functional in other ways, so we think it is "known good",
there is no known reason for the LCD to be toast, so it is presumed
good, the wiring checks out so we think it is known to be good.

The factor that is most likely to be messed up is the wiring despite
the fact you have double checked it. The second most likely is that
the code is bad despite not knowingly having modified it. Or the
combination of the 2: the wiring is fine, and the code is fine, but
the 2 are not using the same pins.

-Tony

--- In basicx@basi..., "naimead" <naimead@y...> wrote:
> Tony,my problem with this LCD is that although i do see black boxes
> the screen i don't see any data that make sense as before!!!Of
course i
> tried to use the contrast but the only thing i managed to do is to
see
> the same black boxes not as faint as before.Is it possible to be
basicX
> problem?I checked the connections i had hard wired on the pins but
> they seem fine!