scrolling text input? for pic18f4520 with 2x16 lcd

[alamakazam]

There is no scrolling text in that video. That is just the cursor showing which digit is to be changed, and a set of buttons to toggle the value of that digit. Is this what you are trying to do? Do you have an LCD setup with the ability to display characters onto it already?

oh yes, I have the buttons and lcd integrated, and is displaying "hello world"

[spcw1234]

You need to create a variable to display that the button will toggle.

Do you have some code started that you can post up?

[Art]

Something like:

value var word
incvalue var word
cursorposition var byte


**LCD setup code here **

LCDOUT $FE, $0F        'turn blinking cursor on
cursorposition = 0    'reset cursor position


dostuff:

LCDOUT #value DIG 3
LCDOUT #value DIG 2
LCDOUT #value DIG 1
LCDOUT #value DIG 0

IF upbutton = 1 THEN
IF cursorposition = 0 THEN
value = value + 1
ENDIF
IF cursorposition = 1 THEN
value = value + 10
ENDIF
IF cursorposition = 1 THEN
value = value + 100
ENDIF
IF cursorposition = 1 THEN
value = value + 1000
ENDIF

IF downbutton = 1 THEN
IF cursorposition = 0 THEN
value = value - 1
ENDIF
IF cursorposition = 1 THEN
value = value - 10
ENDIF
IF cursorposition = 1 THEN
value = value - 100
ENDIF
IF cursorposition = 1 THEN
value = value - 1000
ENDIF

IF leftbutton = 1 THEN
IF cursorposition > 0 THEN
LCDOUT $FE, $10        'move cursor left
cursorposition = cursorposition - 1
ENDIF
ENDIF

IF rightbutton = 1 THEN
IF cursorposition < 3 THEN
LCDOUT $FE, $14        'move cursor right
cursorposition = cursorposition + 1
ENDIF
ENDIF

IF confirmbutton = 1 THEN
'** go back to, or continue the main program here
ENDIF

goto dostuff

[Art]

oops, straight after the dostuff: label,

LCDOUT $FE,2                                    'LCD cursor return home
FOR count = 0 TO cursorposition
LCDOUT $FE, $14        'move cursor right
NEXT count

to set up the display for the next frame.
None of this is tested, but you should get the idea.

[Demon]

Might want to compare cursor position with 0,1,2 and 3 when checking the buttons instead of only 0 and 1 no?

Can you even use cursor position 0? Or does it start at 1?

I think you have them backwards, the units would be at position 3, tens at position 2 and so on.

But yeah, that's a perfect starting point to start building on.

Robert

[Art]

Might want to compare cursor position with 0,1,2 and 3 when checking the buttons instead of only 0 and 1 no?

Can you even use cursor position 0? Or does it start at 1?

I think you have them backwards, the units would be at position 3, tens at position 2 and so on.

But yeah, that's a perfect starting point to start building on.

Robert

Whoops, ... copy & paste & forgot to adjust

IF downbutton = 1 THEN
IF cursorposition = 0 THEN
value = value - 1
ENDIF
IF cursorposition = 1 THEN
value = value - 10
ENDIF
IF cursorposition = 2 THEN
value = value - 100
ENDIF
IF cursorposition = 3 THEN
value = value - 1000
ENDIF

and do the same with te up button.
Also need a pause for button debounce, so

pause 500

straight after each button check
cursorposition = 0 is the thousands position.
The thousands digit is the first to be printed to LCD,
so no movement needs to occur from cursor home command.

[Art]

And the other thing you mentioned...
I need to build a generic test circuit before posting code