LCDOUT on the 16F688

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- 14th August 2008, 15:37
PICante

LCDOUT on the 16F688

Hi all!

On which I/O pins (16F688) can I expect to find the PBP default connections for an LCD (44780)?
Asking since this device doesn’t have any PORT B.

Thanks.
- 14th August 2008, 15:41
skimask

Quote:

Originally Posted by PICante

Hi all!
On which I/O pins (16F688) can I expect to find the PBP default connections for an LCD (44780)?
Asking since this device doesn’t have any PORT B.
Thanks.

Yes, the manual does not define those pins...

Is it so hard to set your own pins for your configuration?
- 14th August 2008, 16:38
PICante

Hi skimask,

No, I would probably manage to set the pins straight but it is against my principals to fiddle with things for no reason (call it lazy if you want!). :-) That’s why I was wondering where to find them on this device as default.
This “project” is at an early stage (on paper) so I am just trying to figure out which pins are available after hooking up an LCD (on the default pins). :-)

Thanks
- 14th August 2008, 17:49
skimask

Quote:

Originally Posted by PICante

Hi skimask,

No, I would probably manage to set the pins straight but it is against my principals to fiddle with things for no reason (call it lazy if you want!). :-) That’s why I was wondering where to find them on this device as default.
This “project” is at an early stage (on paper) so I am just trying to figure out which pins are available after hooking up an LCD (on the default pins). :-)

Thanks

Well, that's one reason to learn why everything works the way everything works...
'cause if you did...you may also find out that on a parallel LCD, you don't necessarily need the R/W pin connected, just tie it low.
There ya go! Saved you 1 pin...
You can actually figure it out for yourself.
Make a program that accesses the LCD, compile it, assemble it, set up MCS to output a .LST file (before compiling and assembling), then search that .LST file for the LCDOUT command. If you look close enough, you should be able to see references in that .LST file as to where the command is going to send data/control signals.
- 20th August 2008, 16:05
PICante

I did lookinto the .LST file but there was a LOT of LCDOUT’s! So I decided (easy way out) to assign pins for the LCD myself and it works perfectly.

Thanks skimask! (and don’t say “I told you so”!) :-)
- 20th August 2008, 17:42
skimask

Quote:

Originally Posted by PICante

I did lookinto the .LST file but there was a LOT of LCDOUT’s! So I decided (easy way out) to assign pins for the LCD myself and it works perfectly.

Thanks skimask! (and don’t say “I told you so”!) :-)

Nah, no I told you so...
Yes, there is a lot of LCDOUT's in the LST file, but the ones you want to look at are the ones before your main program, near the top of the file, where all of the PBP subroutines (not your subroutines) and helper routines go.