Hello all,
     Well I just hit another milestone. I am now using the busy flag=20
instead of a delay loop. The busy flag won't vary no matter the speed of=20
the PIC. The delay loop is longer with lower clock speeds and shorter=20
with higher clock speeds. Yeah!
Thanks,
rich!

On 10/23/2015 5:24 AM, James Cameron wrote:
> Summary: in read_busy_flag you are switching the wrong TRIS
>
> That you removed the call to LCD_set_position and it worked suggests
> something that function does is wrong.
>
> Looking at that function, I'm puzzled by the first two lines;
>
> extern void LCD_set_position(unsigned char position) {
>          unsigned int data;
>          LCD_data =3D data;
>
> It doesn't seem necessary to write the uninitialised variable to the
> register.  But it is probably harmless.
>
> Last thing in the function is to call read_busy_flag, a misnamed
> function because it does more than read, it loops until DB7 is
> true.
>
> Now since all bits in TRISD are cleared, and never set, the read of
> RD7 will fetch the output register bit only, which if it is LOW will
> loop at that point forever, but if it is HIGH will return from
> read_busy_flag prematurely, before the LCD has finished what you asked
> it to do.
>
> Perhaps you intended to modify TRISD instead of TRISA twice in
> read_busy_flag?
>
>
--=20
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