Can defines be changed with port input?

[mister_e]

The LCDOUT defines don't alter the SERIN/SEROUT... it's two different things.

If you want to use the internal USART RCSTA/TXSTA/SPBRG you have to use HSEROUT/HSERIN AND the dedicated I/O.

If you want to use your favourite I/O and don't want to mess your time in calcs, use SEROUT/SEROUT2. these allow to change the baudrate on the fly without too much effort, fat free and allow to use almost every PIC i/o.

And if you want to configure your Serial LCD... i don't know how as you never said wich one you're using

But for sure LCD_LINES is not the solution.

[Archangel]

The LCDOUT defines don't alter the SERIN/SEROUT... it's two different things.

Yes , that I knew already

If you want to use the internal USART RCSTA/TXSTA/SPBRG you have to use HSEROUT/HSERIN AND the dedicated I/O.

This I am already doing and now understand how to shift baud rates . . easy

If you want to use your favourite I/O and don't want to mess your time in calcs, use SEROUT/SEROUT2. these allow to change the baudrate on the fly without too much effort, fat free and allow to use almost every PIC i/o.

No need, serial backpack works great, tweaking to add features.

And if you want to configure your Serial LCD... i don't know how as you never said which one you're using

But for sure LCD_LINES is not the solution.

My real question was, or is : in the <h4>LCDOUT DEFINES</h4> if LCD_LINES 2 has no apparant effect to limit the LCD from displaying more, why is it even used?

[keithdoxey]

<h4>LCDOUT DEFINES</h4> if LCD_LINES 2 has no apparant effect to limit the LCD from displaying more, why is it even used?

In the example code you gave you are sending to a Serial LCD display using SEROUT

LCDOUT DEFINES are exactly what the name suggests...definitions for the LCDOUT command which you are not using!!!

Likewise HSER_ defines are for HSEROUT and will have no effect on any SEROUT commands.

[Archangel]

In the example code you gave you are sending to a Serial LCD display using SEROUT

LCDOUT DEFINES are exactly what the name suggests...definitions for the LCDOUT command which you are not using!!!

Likewise HSER_ defines are for HSEROUT and will have no effect on any SEROUT commands.

I have code for a serial to parallel backpack adapter, so yes i send serial commands to the adapter pic. It in turn outputs parallel LCDOUT commands and it works quite well. The code is designed to accept lcdout formatting commands to position each line on the lcd. It stores hserin data in a variable and then outputs into a standard LCD via LCDOUT. NOW in the lcd Defines which affect the PARALLEL LCD configured as a 4 bit display I have installed the following:
DEFINE LCD_LINES 2. the display seems unaffected when hooked up to a 4 line display, as it continues to correctly display 4 lines of data sent to it. SO THE QUESTION REMAINS, what good is the lines DEFINE if it doesn't limit the output to 2 lines?
JS

[Acetronics2]

DEFINE LCD_LINES 2. the display seems unaffected when hooked up to a 4 line display, as it continues to correctly display 4 lines of data sent to it. SO THE QUESTION REMAINS, what good is the lines DEFINE if it doesn't limit the output to 2 lines?
JS

Hi,Joe

Those defines are written for most common types of displays ...

If using exotic displays ...you also have to verify their commands are those PbP sends when configurating the display ...

Mhhhh, now, If you DO NOT send data one after the other , but specify WHERE you want it to be written ...

Only 2 lines will be used ...

But YOU MUST Tell PbP you USE a 4 LINES Display ... PbP can't think you only WANT 2 lines ... no DEFINE for unwanted lines !!!

CQFD

Alain.

[Archangel]

Hi,Joe

Mhhhh, now, If you DO NOT send data one after the other , but specify WHERE you want it to be written ...

Only 2 lines will be used ...

But YOU MUST Tell PbP you USE a 4 LINES Display ... PbP can't think you only WANT 2 lines ... no DEFINE for unwanted lines !!!

CQFD

Alain.

HI Alain,
The thing is, if you check post #6, I am sending the data in a manner so as to tell PBP where to write each line, I would expect the software to delimit the display to the addresses available only to a 2 line display if it is defined as a 2 line, even with a 4 line display connected, but it displays all 4 lines. Now if I install a 2 line display, and send 4 lines of data as written in post 6, only the lines written for line 1 and line 2 will display. I would have expected the PIC to truncate the third and fourth lines when set to 2 lines, even when connected to a 4 line display. It appears that is not so. So I still have the question, what effect does DEFINE LCD_LINES have on the LCDOUT command?
Regards
JS

[keithdoxey]

OK. I didnt know what the LCD_LINES define actually did so I took a look in PBPPIC14.LIB and located this section of code.....

    if (LCD_BITS == 8)
      if (LCD_LINES == 1)
        movlw   30h             ; 8-bit mode, 1 line, 5x7 font
      else
        movlw   38h             ; 8-bit mode, 2+ lines, 5x7 font
      endif
    else
      if (LCD_LINES == 1)
        movlw   20h             ; 4-bit mode, 1 line, 5x7 font
      else
        movlw   28h             ; 4-bit mode, 2+ lines, 5x7 font
      endif
    endif

The "Function Set" register of the 44780 LCD controller chip has the following bits


D7 = 0
D6 = 0
D5 = 1
D4 = DL
D3 = N
D2 = F
D1 = -
D0 = -

where

DL = DataLength
1 = 8 bits
0 = 4 bits

N = Number of lines
1 = 2(+) lines
0 = 1 line

F = Font
1 = 5x10 dots
0 = 5x8 dots

So looking at the code in the library file, the define is acted upon but is only used to correctly configure the display driver chip for the LCD display connected to it during initialisation.

When you consider that there isnt a define for LCD_CHARS to declare how many characters are on a line then it follows that it cant do anything clever such as work out that you have reached the end of line 1 and move to the start of line 2.

PBP does an awful lot of the hard work for you but there are times when you have to take care of some things yourself.