With 8 bit mode you gain 1us for each byte transfered, which is not much
indeed when compared with the command execution times (37us for each
data byte and most commands, and 1.52ms for "Clear Screen" and "Home
Cursor").

What can save much more time is using the R/W pin and busy flag,
allowing the command termination much earlier than the typical times.

Isaac


On 17/03/2015 12:06, Allen Mulvey wrote:
> LCDs are slow. I doubt if you will gain much from 8 bit mode
> and extra pins tend to be useful. I wrote some simple
> routines for putting strings or characters on the screen
> without using any compiled library. You can find them here:
> http://www.mikroe.com/forum/viewtopic.php?f=3D88&t=3D60600
>
> Allen
>
>> -----Original Message-----
>> From: piclist-bounces@mit.edu [mailto:piclist-
>> bounces@mit.edu] On Behalf Of Matt Rhys-Roberts
>> Sent: Tuesday, March 17, 2015 8:09 AM
>> To: Microcontroller discussion list - Public.
>> Subject: [PIC] Interfacing a 2x16 LCD, using MPLAB-X and
> XC8,
>> on a PIC18F
>>
>> Hi, I'm right at the start of trying to drive a generic
> ST7066U-
>> based
>> 2x16 LCD character display, compatible with
>> HD44780/KS0066/KS0070B etc.
>>
>> Talking to the display can be done using 4 or 8 bits. I'm
> using 8
>> bits
>> for now until I can prove any advantage to using 4. Pin
> count
>> costs,
>> perhaps? Any opinions on this please?
>>
>> It seems logical to use the pre-written LCD library code
>> provided by
>> Microchip, rather than write my own, at this stage. So I
> think I
>> need to
>> include xlcd.h, but then I'm not too clear about getting
> the job
>> done. I
>> can see a number of .c files under
>> /opt/microchip/xc8/v1.33/sources/pic18/plib/XLCD which I
>> guess I'd call,
>> and pass parameters accordingly.
>>
>> So my question is, has anyone seen a good user guide to
>> setting all this
>> up? I seem to have found the details before finding any
> kind of
>> manual.
>>
>> Many thanks,
>> Matt.
>> --
>> http://www.piclist.com/techref/piclist PIC/SX FAQ & list
>> archive
>> View/change your membership options at
>> http://mailman.mit.edu/mailman/listinfo/piclist

--=20
http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist
.