LCD interface questions? SPI? Graphic interface?

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FrAl_4441706
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Hey, me and my friend were able to finish the to record and transmit accurate data using UART. However, Now I'm focusing generating the waveform on a Velleman VMA412 LCD. I posted a question regarding what LCD screen to get, and most of the people on here recommended an Ili9341 LCD display. This VMA412 display I'm using has the Ili9341 V0.7. I was given a schematic by Motoo Tanaka that utilized SPI interface (All credit goes to him, Thank you!). However, I believe that my SPI on my LCD seems to only have SD Cards SPI protocols and not a separate pin to connect to the Master SPI  Component in PSOC (I think this is due to the SD before each SPI protocol pin). I will show a picture of the LCD pins plus the data sheet of LCD . But I connected DS_SCK to the master sclk, MOSI to SD_DI, MISO to SD_DO, I think I connected TFT_CS to LCD_CS. connected VDD and ground. The LCD turns on, I just get a white screen though.  And the other pins on my schematic I still have questions about, As I have no clue to where they go? I looked at the Ili9341 Datasheet but it is 300 pages and I don't think this LCD screen has the same layout as it. Pins IM[0-3] for interface mode are missing! If SPI does not work, I was offered another suggestion by DheerajK to use the GraphicsLCDInt component. However, I think I need to download Segger Emwin library to be able to utlize the 8 bit 8080 communication component. I would also like tips on that! As a last resort. I found a Russian website that featured plenty of examples of Graphic LCD. However, Google translate was not much help and I'm not fluent in Russian.

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Thank You! and any help will be appreciated as you all have been of great help!

Here is the link to the product!

https://www.jameco.com/z/VMA412-Velleman-2-8-320x240-Touchscreen-Display-for-Arduino-Boards_2245474....

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          Credit Goes to Motoo Tanaka for the Schematic, TFT.h and TFT.C!

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1 Solution

The forum had such projects.

This project is similar to yours:

http://www.cypress.com/forum/psoc-5-known-problems-and-solutions/lcd-tft-32-ili9341-use-mode-16-bit-...

I hope someone will tell you where there is more.

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EvPa_264126
Level 7
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I found little information on this display.

It seems impossible to choose an interface.

a few questions:

- Does the display require 2 sources of 3.3 and 5 volts?

- do you use GraphicLCDIntf (8bit) to connect?

  this is my website

Before Using Segger Emwin library

you need to make sure that you have a connection with the display:

- use GraphicLCDIntf (8bit) to connect

- conduct a simple communication test, for example, read the display ID.

- Learn how to initialize the display.

I ordered another LCD display that should have an SPI Interface. I'm not really fond of using Segger Emwin. It seems time consuming and convoluted, albeit really fun to play with once I know the library. The LCD turns on when I connect it to 5V and ground. I don't think I need the 3.3 V, It might be an important pin. But it may be for analog or Back Light I'm not sure. I thought I need to download Segger EmWin to use GraphicLCDintf8 bit? As I need the initialize library to even interface with the LCD screen (To ensure I receive and write data in 8 bit parallel). I can turn on it on but I have no clue on how to initialize or transmit data. I purchased another SPI compatible LCD screen. However, I was wondering I also would like to port the data to MATLAB Also through UART. As working with a graphic LCD seems a little bit outside my knowledge right know, just as a back up.

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It seems the display should be connected as in the figure below.

I hope this is a standard Ili9341 display, prepared for connection to an arduino, 412.pngtherefore, you can use the initialization for this display.

  If you plan to create a project with VMA412 publish it here to make it easier to discuss problems.

The simplest thing is to read the display driver ID:

send the command 0xD3h and read the data 4 times

  in the last two reads it should return the driver ID (9341).

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The forum had such projects.

This project is similar to yours:

http://www.cypress.com/forum/psoc-5-known-problems-and-solutions/lcd-tft-32-ili9341-use-mode-16-bit-...

I hope someone will tell you where there is more.

Hey! thanks for the help! I also obtained this LCD screen from this website to make my life a little bit easier, and use an SPI library.

2.8 inch ili9341 240x320 spi tft lcd display touch panel spi serial port module Sale - Banggood.com

This one has an SPI connection. I was wondering as I'm still knew to LCD displays. If I connect all these pins to the schematic on This board.

and connect them properly using the SPI schematic above. And I still just get a blank white screen. What does that mean? I also have no clue where the LED pin connects to I think it is the backlight? but When I connect VCC and GND I still get no power. But when I connect LED and GND I Get a white light!. Thanks again for the help!

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and here is the PIN Schematic.

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My display connection diagram is attached.

Tell me what kit you are using.

If you publish your project, I can check it out with my display.

Eugeniy

p.s.  https://community.cypress.com/message/157096#1570969341.jpg

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I'm using Psoc 5lp as the kit!

and here is the project!

Thanks for the help. I'm not doing a 3.3 Voltage divider for some of the pins you mentioned for the pictures above. Maybe that might be an issue.

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9341_.jpg

3.3V power via red LED.

For 5V - a white screen.

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I think that I used some large (~200OHm) resistor in series with 5V with same screen to drop down voltage to ~3V.

/odissey1

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