QVGA 2.2 inch TFT SPI 240x320 (ILI9341) is not working! [SOLVED]

[fabianbambam]

Hello People!

I'm interfacing with QVGA 2.2 inch TFT SPI 240x320

My problem is that I was so excited to start interfacing with the TFT that I started to wiring the TFT and test it with the Adafruit_ILI9341 library and the LCD display with ILI9341 driver on Arduino Thread, but it doesn't work, I forgot to check the datasheet of the controller (ILI9341).

Then I looked in the datasheet of the controller and I saw that it needs to be sourced with 3.3V and I was sourcing the TFT Screen with 5V :o

After that I tested the TFT with the 3.3v with no updates, nothing happens. I checked if I have short circuits on the TFT boards but it doesn't have, at least.

So now I don't know if I had damaged the TFT Screen or is just that I'm missing something on the library, wiring connection or code

If somebody could provide me a wire connection to test it with the Arduino Uno
and a Library to make work the TFT, it would be great!

I will leave you here the ILI9341's datasheet

Here's attached hardware's pictures:

I hope to receive some help from you guys

Sorry for my english and best regards!

[bodmer]

See 2.2" display notes here.

If you are using the Adafruit library do not forget to include the reset pin in the constructor.

[fabianbambam]

So according to that, I have to wire the QVGA 2.2 Inch TFT Spi board like this picture? I draw it with Eagle to make easier to understand.

I had noticed about the wiring connections in the instructables:

UNO +5V to display pin 1 (VCC) and pin 8 (LED)
UNO 0V (GND) to display pin 2 (GND)
UNO digital pin 7 through a 1K2 resistor to display pin 4 (RESET), add a 1K8 resistor from display pin 4 to GND
UNO digital pin 9 through a 1K2 resistor to display pin 5 (DC/RS), add a 1K8 resistor from display pin 5 to GND
UNO digital pin 10 through a 1K2 resistor to display pin 3 (CS), add a 1K8 resistor from display pin 3 to GND
UNO digital pin 11 through a 1K2 resistor to display pin 6 (SDI/MOSI), add a 1K8 resistor from display pin 6 to GND
UNO digital pin 13 through a 1K2 resistor to display pin 7 (SCK), add a 1K8 resistor from display pin 7 to GND

[fabianbambam]

I made a test and I got a White Screen as an ouput on the TFT Display, I think this is a good sign, maybe it's going to need some code to get it work

I will test now with the Adafruit library

[fabianbambam]

I still have not get to work the TFT, I have always a white Screen...

My connections are:

All connections are wiring with a voltage divider (less VCC & LED):
arduino pin (5V signals) ----1k----display pin (Approx. 3.3V) ----1k8----GND

TFT----------Arduino UNO:
VCC---------3.3V
GND--------GND
CS----------PIN10
RESET -----PIN8
D/C---------PIN9
SDI(MOSI)-PIN11
SCK---------PIN13
LED---------47ohms----3.3V
SDO(MISO)-PIN12

I also receive a response from serial monitor!

I'm starting to think is a current issue... Any Suggestions? Or maybe another library?

[david_prentice]

Connect the LED+47R to 5V.

You can connect VCC to 5V (if J1 is open). The onboard LDO will provide 3.3V for the ILI9341.
Your voltage-dividers ensure that the ILI9341 sees 3.3V logic.

The Adafruit example should read registers and display on Serial Terminal.
What do you get?

Have you used the full-fat constructor() ? i.e. with PIN8
Adafruit examples use a short form without the LCD_RESET argument.

David.

[fabianbambam]

Thanks for your answer!

Connect the LED+47R to 5V.

You can connect VCC to 5V (if J1 is open). The onboard LDO will provide 3.3V for the ILI9341.
Your voltage-dividers ensure that the ILI9341 sees 3.3V logic

I will try in that way, currently from my voltage-dividers I get 3.2V and I think that's not going to be a problem to see 3.3v logic

The Adafruit example should read registers and display on Serial Terminal.
What do you get?

From Serial Terminal I receive a response, I will attach here

Have you used the full-fat constructor() ? i.e. with PIN8
Adafruit examples use a short form without the LCD_RESET argument.

Certainly not, first I was testing with only running the graphictest from adafruit, then I include the reset:

// For the Adafruit shield, these are the default.
#define TFT_RST 8
#define TFT_DC 9
#define TFT_CS 10

with no results, is that what are you talking about?
Sorry to not understand

[david_prentice]

I would expect to see:

ILI9341 Test!
Display Power Mode: 0x9C
MADCTL Mode: 0x48
Pixel Format: 0x5
Image Format: 0x9C
Self Diagnostic: 0xC0

If you don't get a proper diagnostic result, there is little point in continuing.

This is the full-fat constructor:

// Use hardware SPI (on Uno, #13, #12, #11) and the above for CS/DC
Adafruit_ILI9341 tft = Adafruit_ILI9341(TFT_CS, TFT_DC, TFT_RST);

Adafruit like to omit the TFT_RST argument e.g.

Adafruit_ILI9341 tft = Adafruit_ILI9341(TFT_CS, TFT_DC);

I presume they do this on purpose. So that they can crash every Red Display and possibly sell more of their own Displays. (which have an external pullup on TFT_RST)

Incidentally, I tried the Adafruit example with "their" constructor. I get a White Screen.

ILI9341 Test!
Display Power Mode: 0x0
MADCTL Mode: 0x0
Pixel Format: 0x0
Image Format: 0x0
Self Diagnostic: 0x0

David.

[fabianbambam]

I have good news!

I made it!

I was missing one thing in the code:

I will suggest to follow this steps ILI9341 TFT
This comes from the graphictest from adafruit ILI9341:

// For the Adafruit shield, these are the default.
#define TFT_RST 8   // You have to add this
#define TFT_DC 9
#define TFT_CS 10
 
// Use hardware SPI (on Uno, #13, #12, #11) and the above for CS/DC
Adafruit_ILI9341 tft = Adafruit_ILI9341(TFT_CS, TFT_DC, TFT_RST); // also TFT_RST has to be included to make it work

One thing that I notice is that I maybe have to change the voltage-divider resistors:

5V_Signal-----1k----(Approx 3.2V)----1.8k----GND

Because sometimes the Screen get freeze and I have to reboot the system, also sometimes is showing whitescreen again, is like noise issue. But at the moment is working great!