LCD display acting weird with PIC 18F4450

[Pierre67]

Hello,

I had a PIC 16F887A and I recently upgraded my microchip to a 18F4450 and the LCD screens (EB005 and EB043) that I tested on the chip have some very strange behaviors :
- sometimes it won't display anything (most of time)
- sometimes it displays things but characters are messed up or missing
- sometimes it starts to display my program and then the screen turns blank
- sometime the screen prevents the program from being sent to the chip (If I remove it from the programing board the transfer works)
- this morning I sent the program into the chip, everthing was working, then I sent another program that wasn't working and after that I decided to go back to my working program, so I sent it to the chip but for an unknown reason the exact same program that worked two minutes ago didn't work either... I thought I was becoming crazy !

I think the source of the problem is that the PIC 18F4450 is badly configured, but I don't know how to configure it properly to work with the screen without trouble.
By the way, I'm using Flowcode 5.

Can you help me here ? Can you maybe give me a .fcf file where the screens ( EB005 and EB043 ) are working well with the PIC 18F4450 ?

Thanks in advance !

[dazz]

Hi
Please post the flowchart you are using and we can suggest if theres anything wrong with the chart of config.
check your config is as per the attached pic, bits in red make sure yours mathches
parts in green mchange to match your xtal settings etc

Regards
Dazz

[Pierre67]

It's very nice to have such a good support, you guys are always very reactive on this forum ! Thanks a lot for your quick answer.
Unfortunatly I'm not able to test the config you sent me in attachment until friday. I will try it then and will tell you if it worked or not. If not, I will send you my .fcf file.

Otherwise, you said that :

"check your config is as per the attached pic, bits in red make sure yours mathches
parts in green mchange to match your xtal settings etc"

I'm sorry but I don't get it, could you reexplain that part ? Because I'm french and I don't perfectly understand english..

[dazz]

Hi Pierre
I'm sorry a few spelling errors crept into my post, i will try to explain the settings first the parts in the image outlined in red. Power up timer enabled allows the pic a few clock cycles to get the crystal up to speed, Watchdog time(wdt)r disabled if the wdt is enabled it will reset the pic if its not checked regularily so unless you need it switch it off , Port B A/D enable make sure its set to digital as portb is mainly used for lcd and needs to be digital, Extended cpu/ dedicated icsp and low voltage program need to be off as they can make your pic do strange things.

The parts in green are just a reminder to select the correct crystal source
sorry if this has not translated correctly as my french is very bad and google makes it worse

Regards
Dazz


Salut Pierre
Je suis désolé de quelques fautes d'orthographe glissée dans mon post, je vais essayer d'expliquer d'abord les réglages des parties dans l'image encadrée en rouge. Power up timer permis permet au pic de quelques cycles d'horloge pour obtenir le cristal jusqu'à la vitesse, le temps de chien de garde (WDT) r désactivée si le wdt est activée, elle permet de réinitialiser l'image si elle n'est pas vérifiée regularily donc à moins que vous en avez besoin éteignez-le, Port BA / D permettent de s'assurer que son jeu vers le numérique comme portb est principalement utilisé pour les écrans LCD et doit être numérique, cpu étendue / ICSP dédié et un programme de basse tension doivent être au moment où elles peuvent rendre votre pic faire des choses étranges.

Les parties en vert sont juste un rappel pour sélectionner la source de cristal correct
désolé si cela ne s'est pas traduit correctement car mon français est très mauvais et Google rend pire;)

Cordialement
dazz

[Pierre67]

Well, with your configuration the displays are working again, but only on port D.

Anyway, thanks a lot !