Help with LCD commands with button I/P

[g7jiq]

Hi all,

I am a newbie and I am looking for any pointers on a little problem i have.

I am trying to get a 2 line LCD display to change its display when it recieves a logic input.
(I am using a 2 line display and a 16F627)
I can get it to display anything I want with the LCDOUT command,
My problem starts when I try to change the displayed words when I recieve an input,

For test purposes I attached a button to the input,
The best I could get was the display to flash both commands when the button was pressed.

Any ideas ?

Cheers
Dave...

[CocaColaKid]

Why not just use and if...then statement and use the button to input to toggle between the two display outputs.

[g7jiq]

Hi,

Thanks for your reply,

The program I am trying to get going is to get an lcd display to display the status of a low power ham radio repeater,
The pic's i/p lines will be connected to the control lines of the radio control circuit.

I have re-writen the program using the IF, THEN commands and all I get is the setup message and lcd back light,
The display remains blank no matter what the i/p lines are doing.
(I/P pins are 10k to Gnd.)

The program I am trying to get working follows:-
(please feel free to rip it apart and advise me where I am going wrong)

Cheers
Dave...


TRISA=%00000000 'Set port A as output
TRISB=%01110111 'Set port B as input except B7 for backlight and B3 for lcd

Backlight VAR PortB.7 'Set var as port B7

SW1 VAR PORTB.0
SW2 VAR PORTB.1
SW3 VAR PORTB.2
SW4 VAR PORTB.4
SW5 VAR PORTB.5
SW6 VAR PORTB.6

Pause 500 'stand by for lcd

lcd_light: 'light up lcd backlight
low Backlight

gosub setup
goto loop

setup:

LCDOUT $FE,1 'clear lcd
lcdout " G7JIQ Micro" 'Display on line 1
lcdout $FE, $C0 'Display on line 2
Lcdout " Link Repeater"
pause 2000
LCDOUT $FE, $0C 'turn off cursor
lcdout $FE,1 'clear display
lcdout $FE,2
return

loop:

if SW1 = 0 then Disp1
if SW1 = 1 then Disp2
IF SW4 = 0 THEN Disp3
if SW4 = 1 THEN Disp4

goto loop


Disp1
lcdout "Standby"
Disp2
lcdout "Main"
Disp3
lcdout $FE,$C0,"Local off " 'display on line 2
lcdout $FE,1
Disp4
LCDOUT $FE,$C0,"local on"
lcdout $FE,1


end

[Archangel]

Hi g7jiq,
looks simple enough, without my trying your code. You want Disp1, disp2, to run only when sent there,
your code

Disp1
lcdout "Standby"
Disp2
lcdout "Main"
Disp3
lcdout $FE,$C0,"Local off " 'display on line 2
lcdout $FE,1
Disp4
LCDOUT $FE,$C0,"local on"
lcdout $FE,1

try:

Disp1:
lcdout "Standby"
return

Disp2:
lcdout "Main"
return

Disp3:
lcdout $FE,$C0,"Local off " 'display on line 2
lcdout $FE,1
return

Disp4:
LCDOUT $FE,$C0,"local on"
lcdout $FE,1
return

end

without the colons the program sees your subdirectories as just the next line of code, the returns send it back to the line after the one which calls it.
JS

[CocaColaKid]

I may be wrong but would you not require a gosub in order to use a return? I believe a simple goto would me more appropriate in this case.

[mister_e]

and there's another danger... DISP3, DISP4,, the second LCD will clear the whole LCd display.

[Archangel]

I may be wrong but would you not require a gosub in order to use a return? I believe a simple goto would me more appropriate in this case.

YEP!
Shows how close I looked at the code after seeing what I did see! Must have gotten excited.