3.5" TFT LCD Question

Using Arduino Displays
#1

Hi,

I have purchased this screen & shield though they have not arrived yet...

http://www.ebay.com.au/itm/381579742579?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

Ebay seller gave me a link to the library which I have downloaded and installed.

http://osoyoo.com/driver/3.5LCD_ili9481.rar

I have loaded the test example supplied and just done a verify compile which gives errors...? Just want to be sure I have the right library, any help appreciated.

Thanks.

fontdatatype BigFont[3044] PROGMEM={

^

C:\Users\Phil\Documents\Arduino\libraries\UTFT\DefaultFonts.c:234:14: error: variable 'SevenSegNumFont' must be const in order to be put into read-only section by means of 'attribute((progmem))'

fontdatatype SevenSegNumFont[2004] PROGMEM={

^

Using library UTFT in folder: C:\Users\Phil\Documents\Arduino\libraries\UTFT (legacy) exit status 1 Error compiling for board Arduino/Genuino Mega or Mega 2560.

#2

I had the same problem, just re-install that library from Internet. But better backup the old one if you need and modified one.

#3

Oh ok, where did you download it from?

#4

This one sloud be modified for your display: https://github.com/dgolda/UTFT Next time pleashe use google. It took me to find this only about 40 seconds

#5

Thank you.

Yes, that works now.

#6

Hi,

The mega + display I ordered has now arrived but running any of the sample codes on that library does not seem to work...?

http://www.ebay.com.au/itm/381579742579?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

Display flickers and looks like its trying to do something but nothing ever displays at all,

Could someone please give me some example code showign teh correct paramaters for a mega with this display. (Supplier cant...)

Thanks Phil.

#7

Compare your pcb with the photo on the Ebay link. Compare your pcb with the photo in message #45

If neither match, please find a "better link" and describe the differences in English.

David.

#8

You have a PM...

#9

david_prentice: Compare your pcb with the photo on the Ebay link. Compare your pcb with the photo in message #45

  • Ebay items are as pictured
  • Not sure what you are referring to as msg 45? If its the https://github.com/dgolda/UTFT link, then there are no image son that...?

I just need example code working with a mega...

#10

My apologies. I mixed up the threads. There are several about a Red 3.5" Mega shield

This is the message #45 from a related thread that has an excellent photo (with annotated pins)

The question remains: does your display match the photos in your Ebay link (#5 in this thread) ?

Do the pcb traces match? Do you have Resistor Packs: RP1 .. RP7 ?

David.

#11

Hi David,

Thanks for the speedy response, YES, the image from #45 is the exact one I have! And yes, this IS the exact item in teh ebay pics. And yes there are resistor packs RP1-RP6 (no RP7)

  • Could you please advise best library for Mega
  • Also some example code...
#12

Your Ebay link has this picture: |500x500

I count nine resistor packs numbered RP1-RP7, RP10, RP11.

The photo from vagos21:

I count six resistor packs. I note that the pcb tracks are different. The components are different.

Seriously. I am happy to help but only if I am given accurate information. Perhaps Aussie websites show a different photo !!

David.

#13

Sorry, didnt notice that! Yes the item I have been sent is in fact different to the ebay ad.
Attached is a photo of the item I have which IS teh same as that of msg 45

IMG_20160609_232307.jpg
IMG_20160609_232307.jpg3264×2448 997 KB

#14

There was no need to send an "extra" JPEG. Just say that you matched vagos21's photo.

Please can you read the values on RP1-7. Neither photo is clear enough. They will say something like 102 or 103.

Simple answer is: I hope to get a similar board working with a Forum member (peloxp). Until then, I don't think there is any library that works out of the box.

David.

#15

Really, none exist!

These are all 10k ohms (103).

Thank you for your help. Phil.

#16

I would guess that UTFT should work if you create an entry N for ILI9481 and 8-bit. i.e. dsx[N] = 319 dsy[N] = 479 dtm[N] = 8

Untested.

Or you simply edit the existing ILI9481 entry: dtm[21] = 8

Also Untested.

David.

#17

Hi,

OK, but how and where do I make these changes?

Phil

#18

You could try to use the old code from http://osoyoo.com/driver/3.5LCD_ili9481.rar again to see if this works, I know it will give an error, but you must try this code with an older Arduino version like Arduino 1.0 ... Arduino-1.6.5-r2.

If this works you could look further to find a solution.

#19

From a brief glance at the code in http://osoyoo.com/driver/3.5LCD_ili9481.rar

They have made no attempt to support the 8-bit version. There are several people with this 8-bit display shield.

I can confirm that it "works" the same as the 16-bit shield. i.e. same control pins. It just uses an 8-bit bus (D22-D29) when the 16-bit version uses a 16-bit bus (D22-D37)

If you just change dtm[21] from 16 to 8, it will use the same initlcd.h and setxy.h but with the 8-bit driver. You will use the same constructor: UTFT myGLCD(ILI9481,38,39,40,41);

Untested. I do not have this shield. Please report back with the result.

David.

n.b. dtm[] array is in UTFT.cpp file. Remember that dtm[21] is the 22nd entry in dtm[] 21 is the magic #define for ILI9481 in UTFT.h

#20

Do I have to uninstall current application? Not too keen to do that...

Is there no other way? Surely there has to be a library available for this board...?