LCDOUT custom commands - how to?

[Darrel Taylor]

Hey Steve.

I could be wrong, but I think it needs a fix.

The LCD will Power-up in 8-bit mode, but PBP will still be sending 4-bit.
So each nibble acts as a full command.
If you use $33 (twice), then it will get the "reset" 4 times, instead of $30,$00,$30,$00 ...

Then when it switches to 4-bit mode, it receives an extra nibble from the $20 which puts it out of sync with the rest of the data. By pulsing the E pin once it clocks in another $0 which is a "nothing" command and puts it back in sync.

Like this ...

ManualLCDInit:
    FLAGS=2  ' Void PBP lcd initialisation... it's a nice feature !!!
    PAUSE 500
    Lcdout $FE, $33
    Lcdout $FE, $33
    Lcdout $FE, $20 ' official 4 bit mode
    @  bsf LCD_EREG, LCD_EBIT
    PAUSEUS 20
    @  bcf LCD_EREG, LCD_EBIT

 ; -- rest is the same --

[Archangel]

Hi flotulopex,
Ms Melanie mentioned to make sure all analog stuff is off, I saw no mention of the comparators. That silly 16F88 uses them. One of the harder early 16f series to set up because it uses ansel, adcon and cmcon registers and people seem to miss one or the other.
CMCON=7
JS

[mister_e]

Darrel, i think you're right. My previous work on a regular 44780 controller type so far but will send
3,0,3,0,3,0, and lastly 2,0... so 3 not really needed 0's...

I did something else, but i don't think it will be handy now.

NOW...

    @  bsf LCD_EREG, LCD_EBIT
    PAUSEUS 20
    @  bcf LCD_EREG, LCD_EBIT

yup, or

    @  bsf LCD_EREG, LCD_EBIT
    @  PAUSEUS?C LCD_DATAUS
    @  bcf LCD_EREG, LCD_EBIT

Joe S. The analog comparator are disable at POR on this one. But it's always nice to include the line too as safety sake.

[flotulopex]

It's so cruel: when I think all has been done, you All come with more suggestions and I'm in my office now and will have to wait until this evening to try all this out ;-)

Okay Joe, I'll try this one. You're right, some settings on this PIC can be tricky if we forget them.

Darrel, you're far ahead of what I'm able to understand. It sounds so clear for you. What shall I do, replace Mister_e's $30 by your $33?

Merci Steve, it will be easy to copy/paste and check quickly.

Come back to you later.

Thank you All.

[flotulopex]

Until I can try all what you suggest, I would like to understand how you Guys read and interpret the codes in the Initialisation Table I put in my post #19. It looks so obvious to you, unfortunately it is not to me...

As an example, I would like to know how you come to a LCDOUT $FE, $0C to switch On the display.

In the table the line sais Display ON/OFF, you see the bits RS(I don't even know what this one is for) and R/W, and then you have for each DB7...0 a value (0 or 1). Finally you've got this $0F value which appears to me as coming from nowhere.

I admit that the $FE is a standart value for sending datas to the display.

But, in this example, where comes the $0C from? I'm lost...

I'm missing this very basic stuff and bothering you with stupid questions so was this discussed in antoher thread already?

[Archangel]

But, in this example, where comes the $0C from? I'm lost...

Hi flotulopex,
No question you do not know the answer to is stupid.
$0C - listed in PBASIC PRO MANUAL page 94. $0C = Cursor Off
JS

[flotulopex]

Hello Joe S.,

I read this document (PBP manual) almost any time I have a question but I sometimes don't understand the explanations.

As you mention, the actual $0C value listed in the manual switches the Cursor OFF; Mister_e sais that, according to the table, it switches the Display ON. There is a difference.

Mister_e must have interpreted the table; this is what I would like to be able to do too.

So, my question was more precisely to:
a) understand the definition table (in post #19);
b) learn how to use the informations on there.

I don't know how to express myself more clearly but if my question looks confusing, please tell me.

[keithdoxey]

As you mention, the actual $0C value listed in the manual switches the Cursor OFF; Mister_e sais that, according to the table, it switches the Display ON. There is a difference.

Mister_e must have interpreted the table; this is what I would like to be able to do too.

So, my question was more precisely to:
a) understand the definition table (in post #19);
b) learn how to use the informations on there.

Look at the datasheet for the LCD controller, specifically Page 26.

"Display On/OFF"

The 8 bits for the register = 00001DCB

D= display 1=on 0=off
C=cursor 1=on 0=off
B=blink cursor 1=on 0=off

so "00001100"

Will give Display On Cursor and Blink off which is $0C

$0C is the command to turn the Cursor OFF but it also turns the dsipay on as well

$0E will turn the display on with a cursor