LCDOUT probs

[Jhdgkss]

HI there this is the first time i have tried driving an lcd i have read the manual but i still canot get the thing working.
Here is my code

start:

pause 1000 'wait for lcd to start up
lcdout $FE, 1 'clear screen
lcdout $FE, 2 'return to home
lcdout $FE, 1, "Welcome" 'write welcome on the screen

pause 2000

goto start
end if


i have built the circuit based on the one in the pbp maunal

but still no luck, nothing, i have checked all my connections but still nothing the lcd i am using is from here http://www.maplin.co.uk/module.aspx?...9&doy=9m3#spec

please can some one please steer me in the right direction, thank you for your time.

[Charles Linquis]

Make certain you have all your DEFINES set up properly to tell PBP just
what pins you have connected to what.
Also, use some command and data delays.

Below is a header file I use. It works with every display I hook up.
You will have to change your pin definitions, of course.

DEFINE LCD_DREG PORTH
DEFINE LCD_DBIT 0
DEFINE LCD_RSREG PORTH
DEFINE LCD_RSBIT 5
DEFINE LCD_EREG PORTJ
DEFINE LCD_EBIT 2
DEFINE LCD_RWREG PORTH
DEFINE LCD_RWBIT 4
DEFINE LCD_BITS 4
DEFINE LCD_LINES 2
DEFINE LCD_COMMANDUS 3000
DEFINE LCD_DATAUS 300

[skimask]

start:

pause 1000 'wait for lcd to start up
lcdout $FE, 1 'clear screen
lcdout $FE, 2 'return to home
lcdout $FE, 1, "Welcome" 'write welcome on the screen

pause 2000

goto start
end if

Is that your whole program?

[Jhdgkss]

yes thats the whole code. how do i set the define's so that my data will use portA like in the manual and the enable is on portb.3 i thought it would just adopt the standard setting automatacly unless told otherwise. iam useing a pic64f84a

[Charles Linquis]

Just follow my example. It should be pretty explanatory.

In my example, I use PORTH as the data register
The LSbit is tied to bit 0 (PORTH.0)

The R/S pin is tied to PortH.5

E is tied to PORTJ.2 etc

[hoopstar]

Charles,

Is there any particular reason that the 4 data bits and the controlling pins (ie. E, RW, RS) should be on different ports as I seem to see in most examples??

Or can they be "defined" to the same port without problem?


Hoops

[Charles Linquis]

They can be defined on the same port. The only limitation that I'm aware of is that the DATA lines must start on a nybble boundary (either on bit 0 or 4)of a port.