Jon Petty wrote:

> The lcd prints fine, a little dark when set for 1x16 mode, but
> lightens up when I tried the 2X16 mode (for the heck of it), but still
> only prints 8 characters. I tried another display (same type) and it
> doesn't change.

> I am in 4 bit mode and I believe I've tried every config.

  Bit confusing here.  There are no "1 x 16" or "2 x 16" modes, there is
a one-line mode and a two-line mode.  Which is it, and more particularly
how many lines and characters is the display?

  Darkness depends on the contrast control.  You do *have* a contrast
control fitted?

> Help 1X16 LCD only prints 8 characters!

  It sounds like you mean you have a 16-character 1-line display.  These
are (all?) implemented electrically, due to the chip architecture, as a
2 line by 8-character display.  They require setting up in two-line
mode, and the address of the start of the second line is $40.

Kevin Fisk wrote:

> I think you have to print the next 8 characters like they are on the
> second line (this is just from memory from a long, long time ago).
>  I'm sure others will correct me if I'm wrong.

  You're dead right Kevin, you must *set up* 2-line mode, and write
accordingly.

Todd Peterson wrote:

> On some 1x16 displays the right half of the display is mapped to the
> 'second' row in memory - you'll need to perform a cursor move to reach
> them (see module datasheet).

  Todd, can I quiz you on the word "some"?  Since to do so means adding
an extra chip and only using half the capability of each, have you
*ever* seen a display which *didn't* map as two lines?  They certainly
may exist, but would be special ones using the extended-height (11 pixel
high IIRC) character set, presumably LARGE displays.

Ryan Pogge wrote:

> did you get it from BG micro?
> cause i think thats the one i got that does the same thing....
> when you init it the whole top line goes dark black.
> thats all i can get it to do ..hehe

  Your reference to "whole top line" suggests to me 1} you have a two-
line display, 2} you are only initialising it for 1-line display and
2} you have the contrast control set wrong.  You *DO* have a contrast
control fitted, don't you?

  Frankly, the instruuctions for these things, *when* you find them
(I'll quote the sites again on request - really *must* put them on my
web page!) aren't terribly easy to understand.
--
  Cheers,
        Paul B.