|Now after having looked at the datasheet for the controller i see it
|says the controller (hd44780) by itself can driver 1 x 8 lines or 2 x 8
|lines,  i assume that since my lcd modules only has one chip on it, that
|the 16x1 display may really 2x8 lines next to each other. is this
|true???

You are very observent; most cheap 1-line displays are indeed wired
like that, precisely to save the cost of adding another display
driver chip.  The few single-line displays that aren't wired like
that cost more (because of the extra chip) but have better visibil-
ity (because of the 1/8 duty cycle).  Note that when operating such
displays in single-line mode, the LCD drive voltage should be lower
than for 2-line mode.

The following is a list of all common display configurations:

[A] One line, up to 40 characters, either 7/8 or 11 dots high.

[B] One line, up to 80 characters, split into a left and right
    half; the controller needs to be set for a 2-line display
    and the right half is addressed as a second line (starting
    at DDRAM address 0x40, which means you use command 0xC0 to
    start putting data there).

[C] Two lines, up to 40 characters each; this is the most common
    format, and it's programmed just like it looks.  As in [B],
    the second line starts at address 0x40.

[D] Four lines, up to 20 characters each; this is accessed like a
    two-line display that wraps back to the left.  Since the top
    two lines of the display have to share column drivers with
    each other (and so do the bottom two) the third line of the
    display appears as a continuation of the second, and the fourth
    as a continuation of the third.

[E] Four lines, up to 40 characters each, using two controllers.
    The display is basically wired and controlled as two indep-
    endent two-line displays whose controllers share all the CPU
    pins except for Enable.

|also if this is the case is the start of the second line at 0x028???

Address 0x40 (hex), not 40 decimal.


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