ILI9341 with SW/HW SPI, 8/16 Bit parallel mode

daro · Joined: 15 Nov 2010 Posts: 25

Hi, I buy this module shield: https://www.aliexpress.com/item/LCD-module-TFT-2-4-inch-TFT-LCD-screen-for-Arduino-UNO-R3-Board-and-support/32930176014.html

And this module seems to have connected Touch pins with control&data pins of TFT.

After fast recognition:
- Touch Y-(YD) connected to TFT LCD_CS
- Touch Y+(YU) connected to TFT LCD_D1
- Touch X-(XL) connected to TFT LCD_D0
- Touch X+(XR) connected to TFT LCD_RS

Is possible to use this module witch this library?

It probably makes it impossible to use TFT and Touch in the same time?

I read this post https://www.mcselec.com/index.php//index2.php?option=com_forum&Itemid=59&page=viewtopic&p=68399#68399 and I\'m not first who meet this problem.

Question to Plons...How to declare and chose pins where Touch is connected in version witch shared pins TFT?

Netzman · Joined: 25 Nov 2005 Posts: 131 Location: Graz

@hobby this module looks like it has integrated the level shifters, so should be safe running on 5V.
The reset-pin overlapping with CS is not intended, that's an oversight when translating my xmega environment. However, the reset pin assignment is freely choosable by creating the constant before including the library.
The MIKROE Proto Display is the one I've used developing this driver, so I can confirm it works. The D/C pin is used as clock line in serial modes.

@daro quite certainly there's no problem using the display library itself with shared analog/digital lines, but there is no direct support in the library to also use the touch function in such a configuration.
But maybe you can modify Plons' version (shares WR, D/C, D6 and D7 with touch inputs)? Basically you connect the lines to the ADC pins and alternate their configuration between digital outputs for the display and analog inputs for the touch sensing function.

Br

hobby · Joined: 12 Apr 2004 Posts: 109 Location: Brussels

Hi,

I have canceled the using chines product, it's not sure. I have not see the level adapter on PCB.
I'm just focusing on the screen of MIKROE.
I use MEGA 2560 with 3V3 power, for testing is more sure.

I use the Software SPI on portk:
I connect K.0 to RST pin on screen (for Reset) with pull down resistor
I connect K.1 to WR pin on screen (for DC)
I connect K.2 to CS pin on screen (for CS)
I connect K.3 to SDI pin on screen (for SDO)
I connect K.4 to RS pin on screen (for SCL)
I connect IM0 to GND
I connect IM1 to IM3 to 3V3
I connect DB0 to DB17 to GND
I connect RD to GND
LEDK to GND
LEDA to 3V3 with resistor.
TE and SDO is open

I have used the example on wiki web site and just remove the picture code for quick compiling.
I attach the example.
I have added small code for blink led portb.7 (testled sub).
The led blink for line 60 after never.

I use bascom 2.0.8.1 (i can down version).
Another thing, I saw that there are 2 versions of the screen:
MI0283QT2 (Rev 1.x) and MI0283QT9A. (Rev 2.0)
I use the Rev 2.0.

Thanks for your help.
Olivier

Bernd100 · Joined: 12 Mar 2020 Posts: 1 Location: Bayern/Opf.

Hallo Netzmann,

wirklich tolle Arbeit. Inzwischen gibt es auch sehr interessante 3,5" Displays mit dem ILI9486 (SPI) die ursprünglich für den Raspberry gedacht waren.
Hast Du evtl. eine Anpassung (Workarround) für diese Displays?

Viele Grüße
Bernd

Netzman · Joined: 25 Nov 2005 Posts: 131 Location: Graz

Hallo Bernd,

Vielen Dank Smile

Entschuldige dass ich weiter auf Englisch antworte, dann können alle mitlesen.

At a first glance, the ILI9486 seems to be compatible to ILI9341 in most parts. It supports the same interfaces (and some more), they share the same register subset and addresses, memory is organized the same way.
It also includes a PWM generator for backlight control, so that could be offloaded to the 9486.
Surely the initialization sequence with all the power control and gamma settings and, if needed, the constants Lcd_width/Lcd_height must be changed, but the rest should work the same.
You could extract the sequence from those linux drivers (or maybe there is an arduino library?), like I did for the 9341, if you need assistance let me know.

Best regards

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

hi Netzman