Recomendation for graphic LCD/TFT

Hypno · Joined: 27 Dec 2005 Posts: 12 Location: Lublin

Hi, I would like to ask you for suggestions.
I need a 3.2 "- 4" graphic display in my design. Resolution sure 320x200 or 480x320. Other parameters are not important. Actually, the most important thing is size in the given range. If possible, it would be good for the LCD to have an SPI controller, but this is not necessary. I use a Mega2560 processor in the project.
I want the display to support the touch panel and it is best to have the panel included in the set. Now it is not a problem but I have requirements for the touch panel itself. Namely, because the system is to be energy efficient, then for 99% of the time the peripherals will be in sleep mode, including the processor and wake up with interruptions from the RTC clock. I would like it to be the same with the touch controller, which can generate an interruption when touched, and for the remaining time of inactivity save maximum current. I know there are circuits used in other languages for controllers. The LCD price is also important because I plan a series of such devices and I want to have low costs if possible.

And here is the question, what display would you recommend, of course, it is about models that have BASCOM libraries to support.

(BASCOM-AVR version : 2.0.8.2 )

Paulvk · Joined: 28 Jul 2006 Posts: 1257 Location: SYDNEY

I am working with a Nextion display at present.
It has a RTC built in , it is controlled by rs232
it handles all the graphics the avr just needs to send and receive commands
you upload bit maps to it so very professional display can be had

Regards Paul

Duval JP · Joined: 22 Jun 2004 Posts: 1161 Location: France

hi,

Pikczu · Joined: 22 Jan 2006 Posts: 72 Location: Dublin, Ireland

I Personally would recommend 4D systems.
Models with Diablo 16 processor.
Unfortunately, they are not cheap at all( and you need the licence to get all fancy stuff).
But that is only my personal point of view, I had (still have )the cheap display and I have learned the lesson.
4D systems have greate tool for graphic design:
https://www.youtube.com/watch?v=81cez-Ws4dQ
Library is also avaiable.

Hypno · Joined: 27 Dec 2005 Posts: 12 Location: Lublin

NEXTION is probably my discovery Wink

Thank you for the information.

Epaper are at comparable costs and the functionality is incomparable ....

As for the sleep mode, my device consumes 8uA of current, so the mA values are gigantic for me ...
But this is not a problem, I use low-flow converters for power supply, which after cutting off practically do not consume electricity, so I will control the power supply, and because the whole is only woken up properly to the configuration so it is not a problem.

I applaud that I was able to design (mega640pa-au, RTC, EEPROM, 1 Wire, LCD, + sensors) and program that on a 6V / 1.2Ah battery it has been running for over 2 months and has sent over 4,000 SMSes with measurements (Fibocom G510-Q50). Test system set up to send 160SMS messages a day (I want to see how much will be successful). Normally it is sent max 4-8 a day.

Hypno · Joined: 27 Dec 2005 Posts: 12 Location: Lublin

Paulvk - Poul,

I would like to contact you. Can you write to me at hypno(at)poczta(dot)onet(dot)pl ?

Piotr

Hypno · Joined: 27 Dec 2005 Posts: 12 Location: Lublin

With your advice, I bought a NEXTION display. I also bought a 480x320 display with touch on the ILI9486 controller controlled by SPI.
https://www.waveshare.com/4inch-tft-touch-shield.htm
I would like to share some comments with you.
1. NEXTION.
The most important attention I have to him is the issue of UPDATE software. I am not talking about the firmware, but the program we will create using the proprietary NEXTION editor. While for people using this display for prototypes further considerations do not matter, someone who wants to produce a commercial series will already have a problem. And the point is that uploading the new version of the software is not secured in any way. This means that all you have to do is put a card with another program in the slot (access to the menu editor is free, after all) and the display will start the program. Of course, for this "hacker" version to make sense, its creator must know the logic of my program, variables, etc. But you can make useless without any problem ...

2. ILI9486 on SPI
Beautiful but ... terribly slow. I connected it to a mega2560 with a 16MHz clock. So for ATmega it can't be better. I downloaded a professional library from the German forum and added one loop to draw 800 lines in the demo program. The set needs about 20 seconds to draw these 800 lines !!! It takes a few seconds to draw a meaningful menu on such a screen. I wonder what is the point of using such a display. And here a question and a request to you. I mean to someone who uses a 480x320 LCD with some controller but connected in parallel, preferably 16 bit. Could anyone do such a simple test? I mean a simple drawing loop, say 1000 lines between points on the periphery diagonally? He would like to check how much such a system can draw lines 2 within 1 second.
Of course, the considerations relate to BASCOM, although I wonder how much you can squeeze from this LCD over SPI by writing the code in C or ASM.

Paulvk · Joined: 28 Jul 2006 Posts: 1257 Location: SYDNEY

You can make it very difficult to get to the sd card slot or have a warning that trying to load new software will disable the system.
It is possible to put a identification on start up to confirm it has correct display software.
Depending on how many you want to use it may be possible to have a software change made that requires a password from the connected micro.
As you found such nice graphics is not really possible with a dumb display.
Regards Paul

Hypno · Joined: 27 Dec 2005 Posts: 12 Location: Lublin

The fact that my processor recognizes the wrong version is true, but as far as I know, it is not possible to block the password from updating with any password. I contacted the producer in this case and unfortunately confirmed it.
I can hinder access only mechanically blocking access to the memory card slot. I cannot do electronic modification without losing my warranty.
For me it is acceptable. I write about it so that others would be aware of it Wink

Other questions about ILI9486 and SPI or parallel communication remain open and I would love to hear other opinions.

Duval JP · Joined: 22 Jun 2004 Posts: 1161 Location: France

hi
I have used a lot of graphic displays from the venerable ks0708 and then the T6963 240 x128 monochrome to the SSD1963 parallel. all are very very slow!
you won't get anything better than what the specialists at the Bascom forum have obtained
https://www.mcselec.com/index2.php?option=com_forum&Itemid=59&page=viewtopic&t=13074

I switched to HMI with a preference for Nextion for simplicity and price.
The 4 D systems look more professional.

These displays are very fast and easy to use.
Again Paul or I are available to help you.
The include file I wrote allows you to build applications very quickly. even my english is not "academic"

https://www.mcselec.com/index2.php?option=com_forum&Itemid=59&page=viewtopic&t=14537
jp Wink

Hypno · Joined: 27 Dec 2005 Posts: 12 Location: Lublin

I will add my penny ...
In the link below the library for the newer ILI9481, ILI9486 and ILI9488 drivers.

https://bascomforum.de/index.php?thread/1064-3-5-tft-320x480pixel-mit-ili9486/&pageNo=1&s=788cf76fad1a0585a775e1210936ece8de9b6df3

Duval JP · Joined: 22 Jun 2004 Posts: 1161 Location: France

Would you please give your code to display lines,
I wil try under Nextion to see the speed
I use the same way that mister Display :H. Kipnik ! Wink

JP

Hypno · Joined: 27 Dec 2005 Posts: 12 Location: Lublin

I understand that it is all about the loop that draws lines.

The result with a stopwatch in hand 26 seconds ..... for these loops ... Sad

Duval JP · Joined: 22 Jun 2004 Posts: 1161 Location: France

well,
I think this video is a good exemple

https://youtu.be/gmMBj3w6F0Q

I modified the code as :
this page is empty for me
I have to modified the name of variable

Hypno · Joined: 27 Dec 2005 Posts: 12 Location: Lublin

Is the macro written on NEXTION or is the via RS command sent?
By eye 5x faster ....