LCDOUT custom commands - how to?

[mister_e]

I'm using PBP. Where did you find the correct syntax to use for every fuses?

If you're using PM, open m16f88.inc file in c:\pbp\inc folder, they're located at the top.

If you're using MPASM, open p16f88.inc file in C:\Program Files\Microchip\MPASM Suite folder. They're located at the bottom.

There's a huge thread Here about that.

[flotulopex]

Thanks Mister_e,

Fuse config is now clear to me ;-)

Back to my display, I did what keithdoxley suggested but still it's not working.

Finally, I connected my usual display on the PIC with an 8 bit data-bus. It works fine so, for sure, the PIC is not the problem.

I have contacted ELECTRONIC ASSEMBLY and asked for more informations. I still can't believe I would have broken both displays...

For normal use, the display must be set in Read or Write (R/W)?

One last thing about the contrast control: would be the syntax to change the contrast's setting "LCDOUT $FE, $74"? According to the table (Initialise_LCD.bmp) in post #10, it should but how to change the amount of contrast???

[mister_e]

Thanks Mister_e,

Fuse config is now clear to me ;-)

You're welcome, It's always handy to have theses in your code.

One last thing: for normal use, the display must be set in Read or Write (R/W)?

Unless you want to read from your LCD (Wich i still don't understand why anyway) you should set the PIN to 0, low, gnd.

[flotulopex]

Yes, really handy. Thanks a lot again.

I would appreciate to find some more explanations on how to read (understand) and write to the display the configuration commands such as LCDOUT $FE, xxx.

Merci encore.

[flotulopex]

I've got an answer from ELECTRONIC ASSEMBLY (EA). They say this display is fully HD4470 compatible.

So, until the contrast (all the display in fact) is not initialised properly, nothing will happen on the display.

I've got this table extracted from the PDF file I inserted in my first post:


This example is for a 8 bits display. I would prefer to use it with 4 bits but if it is easier to start this way...

Can somebody tell me what syntax I have to use to modify the contrast settings?

Is it LCDOUT $FE, $74? I tried this already but nothing happened.

I don't understand how to use this table. Could somebody explain me please?

BTW, EA also sent me some assembly examples (see attachments); for those who understand this, it may help, maybe. Unfortunately, I don't know assembler...

Mister_e, see the picture? Thanks you, again ;-)

[keithdoxey]

Take a look at http://www.lcd-module.de/eng/pdf/zubehoer/st7036.pdf

Pages 34-38 tell you exactly what each register contains and what each bit does.

Page 39 shows 8 bit initialisation

Page 41 shows 4 bit initialistaion but you dont need to go down to that lave. PBP should take care of that for you.

Just look for the commands that set the contrast. It look to be "$7x" where x is the setting 0-F for the 16 possible values.

I would follow Steves advice for leaving a long delay after the first initialistaion command then try something like this

contrast             var byte
contrastcommand var byte



For contrast = 0 to 15
   contrastcommand = $70 + contrast
   LCDout $FE, contrastcommand
   pause 10
   LCDout $FE,1, "contrast=", DEC2 contrast
   pause 1000
Next

That should send all possible values to the LCD for adjusting the contrast and if it works you will see on the display the values that give a visible display. Then pick the best one.

Cant really offer much more as I dont have that type of display.

[flotulopex]

Okay.

I'll go back to my breadboard and try.

Come back asap.