2,4 TFT LCD with SC Card + Barometer on a Uno

Hi guys,

i need your help.

I have a 2,4 TFT Display with a SD Card slot and a Barometer. I want to build an weather station thats shows some pictures at some weather conditions.

I started the project with my UNO but now I see, that I need second PINs for the SCL and SDA because the SD Card needs this two and the Barometer.

Can you tell em which Board I should use for that?
I though about a MEGA so I can use a TFT LCD Shield and don't have to solder the display but that board has only one SDA/SCL too.

Thanks for your answers

That does not sound correct.

You should post links to the specs of the components you want to use. Please read the forum guide in the sticky post at the top of the forum section to learn about things you should include in your post.

Sure thing.

Here is the display:

And here the Barometer:

Can you tell me where it says that this display needs to use the SDA/SCL pins?

looks identical to the ILI9341 touch display I use - try the Bodmer/TFT_eSPI library
the interface is SPI so you can use I2C for the BMP1`80

would not recommend using such a display with a UNO or other 5V logic microcontroller - I tend to use ESP32 modules

I2C is a bus, theoretically capable of handling 127 different periferals.
Different addresses is the solution.

For the SD Card slot I need the Pins on the right side, or am I wrong?

Your right or my right?

Why do you think those pins should be connected to SCL/SDA?

I though the pin called SD_SCK should go to the Clock Pin?

Yes, the SPI clock pin.

Not the i2c clock pin.

Ahh thanks, that's why I find more esp32 tutorials for this than Arduino :slight_smile:
I didn't want to buy an extra board

on my display the pins are labeled SD_CS SD_MOSI SD_MISO SD_SCK so I would guess they are the SD card SPI interface - never tried it out though

Okay so the SCK is not the for.the Clock Pin?

Incorrect. It is for the clock pin, as I explained in post #10.

Okay, I not that experienced sorry for asking again..with this board (Uno) it's not possible to connect this display and a barometer?

I can't see a reason why not. The display, including the SD card, use the SPI bus. The barometer uses the i2c bus. Uno has both SPI bus and i2c bus.

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Okay, after some research I think I got it:

Here @PaulRB answered already my question

And with this tutorial, it should work

certainly it is possible

however, if you look on web sites which sell this type of display, e.g. 240X320 Resolution 2.8" SPI TFT LCD Display Touch Panel ILI9341 with PCB 5V/3.3V STM32 you will find the statement
Note:
If you are using this LCD with a 5V device such as an Arduino, be aware that it doesn't work if WITHOUT level shifting to 3.3v logic. Please use level shifters from 5V to 3.3V, it will work then
indicating that if you interface this display to a microcontroller using 5V logic, without using level shifters, you may damage the display

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I use resistors to bring the 5V down to ~3V. Isn't that enough to protect the display?

Yes, enough to protect the display while you find out if it works.

You need to use 2 resistors to make a voltage divider. 4K7 and 10K are often used to reduce 5V down to approximately 3.3V. You will need one pair for the SCK line and one pair for the MOSI line.

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