Why does it not work, getting annoyed with this

Using Arduino Displays
1

I recently bought a 2.8" tft screen spi for a project i am working on with arduino.
But i just can't get anything working on the screen
Screen i bought:

http://www.aliexpress.com/item/2-8-inch-spi-interfaces-for-a-variety-of-microcontroller-development-board-for-arduino-UNO-R3/32319840893.html

The seller of the product sended me his code, i plugged my tft screen on the uno like he did and still i don't get anything on the screen...

Attached is the code he sended me.
All i get is a black screen and nothing shows up on the tft screen.
Anyone got any suggestion cause i am getting realy pissed off because of this...

graphicstest.ino (9.07 KB)

2

Is your backlight on TFT working? When the backlight is on the display is usually all white.

3

Its just plain black, nothing shows up.
No backlight, just looks like when you have your pc monitor turned off
That is what it looks like at my screen

4

I had seen this display on AliExpress.

From the photo of the pcb, I concluded that it was an experimental "device" that probably did not work at all.

What country do you live in?

I can look at the attached sketch later this evening. And compare it to the photo of the pcb.
Please can you compare the item in your hand with the AliExpress photo.

Report back if it is a 100% exact match. If it is different, it is not worth our time trying to see what is happening.

David.

5

I live in the netherlands,

Thank you, as far as i can see it is a 100% exact match.
I only just dont understand how it "works" on his photo, and while i attach it to the same arduino as he has mine doesnt do anything :confused:

If this won't work, do you got any other suggestion for a better screen?
I need one that leaves at least analog pin 4 & 5 free (for i2c) because i need to interact with other arduino's for my project. But all of the bigger screens or same size i see all are using all of the available analog pins :confused:

6

According to one of the "feedback" comments, you need Adafruit_ILI9340.h library and not the Adafruit_ILI9341 library.

What is the part number of the SOIC chip?
Are the SMD resistors really 0R ?

Regarding I2C. Most of the current 2.4" MCUFRIEND Shields are using an ILI9341. This means that you do not need the RESET pin. (You can use a Software Reset command with the ILI9341)

So you can simply snip the LCD_RESET male header pin. Now you have A4, A5 freely available for I2C: SDA, SCL. And you still have the Touch Screen and microSD. And those 2.4" Red Shields are CHEAP, reliable and have proper level translation.

David.

7

I tried using the ILI9340 library no luck...
I tried using the ILI9341 library no luck...

Let me see about the SOIC chip (hope this is the correct one...); 22LT3HM CD4050BM

SMD Resistors: can't find anything about that on the tft screen. maybe i am not looking good enough but just can't seem to find anything about that :confused:

8

The SMD resistors are the little black squares R1-R8 near the SOIC chip U5.

0R means zero ohms. i.e. a wire link.

Since you have a CD4050 chip, this should look after the 5V 3.3V level translation.

OTOH, the Arduino's 3.3V pin is unused. And the pcb has not got a 3.3V LDO regulator installed.

It probably picks up VCC from the 16U2 ISP header. (the 3x2 female header)

David.

9

it says 0 on those small chips.
i managed to get back light or how u call it.
not by plugging it into the arduino but by using jumper wires connected to the tft and then to the arduino.
only now i just need to figure out how to display something on it (code that would work)

10

Does this display need 5v-to-3.3v level shifters on the SPI lines? I've bought two small SPI LCD's on eBay and they both required level shifters to work. I used CD4050 chips with both of my LCD's to get them working.

Matt