Tag Archives: tft

STM32 Project – Digital Photoframe

This is our first advanced project using a powerful 32bit MCU and all sort of modern technologies like Colour QVGA display, Micro SD Card and Embedded file system. We have made several project using 8 bit PICs and AVRs but those were simple and didn’t use modern displays. In today’s world every one owns several gadgets like cell-phone, tablets, media players, hand held gaming device, digital cameras that uses TFT LCDs and uSD storage. So I thought current DIYers should be dreaming of using them in their own design too. This created the need for a DIY project that should help experimenters use such technologies. So I designed a simple ARM project called the "STM32 Digital Photo Frame". Project Description You need to place some BMP format images in the folder "slideshow" in the root of MicroSD card. After that install this MicroSD card in the card slot. Then power up the board using a USB Port. The images will be shown on the QVGA TFT Screen one by one. Their will be an approximate delay of 2 seconds between display of each image. Once all the images have been displayed, the sequence will restart from the first image. The slideshow will continue until the power is removed. Note: In the current version, the BMP file must be 24 bits […]

A Basic Touch-screen driver for STM32

Today I completed the basic touch screen driver. The task included Learning the "Theory of Operation" of 4 wire resistive touch screens. Learning the about the working of AD7843 touch screen controller IC. Learning about the SPI peripheral of STM32 Writing basic SPI drivers (to init, read and write to SPI1) Writing basic drivers to command and read AD7843 touch screen controller. Filtering the touchscreen data using Median Filter to remove noise. Learning about the three point touch screen calibration method. Writing a routine to convert touch screen co-ordinate (ranges from 0-4095 in X and Y direction) to LCD co-ordinates. Finally ploting a cross-hair at the touched point. The final result is shown below. Then I moved on to implement a GUI 3D Button. After that I went to try a “Free Hand Drawing” application. And what I made is shown in the video below.

Got the TFT LCD + STM32F103VE MCU Up and Running !

Hi All, I was working to interface 320×240 pixel TFT LCD based on ILI9325 controller with my 32 bit ARM MCU (STM32F103VE). Got to digest the whole datasheet of ILI9325, Learn about the FSMC (Flexible Static Memory Controller). Finally succeeded in initializing the LCD and writing to the GRAM. Then ported a part of ProGFX (Text and Font unit) to this new platform. Finally was able to write text on the LCD Screen. This is part of a bigger project to port BASIC language for STM32 MCU based single board computer with on board LCD and SD card. The user then can program in BASIC language, store .BAS files on SD card and execute on board. Something like a power packed Arduino for the modern world (TFTs, SD Card and Multimedia!) Now the next part is to get a basic GUI up and running to view and load BAS files from SD card. After that main task of porting basic begins!

Microtouch – 2.4 by Adafruit and Rossum

I found this amazing stuff today morning. I haven’t tried it yet, but It looks like a perfect solution for using TFT and Touch Screen with AVRs. I mean perfect because its more than a hardware. It promises a nice Application Framework (kind of like MFC for AVR), Low level driver for TFT and Touch screen, A windows simulator for rapid application development. TFTs and Touch screen are sold by many these days but rarely any of them are of any use (because of lack of Application framework and other tools) Will surly give it a try when it comes in stock. Microtouch Official Page At first when I saw the Video, I thought It was fake. Smooth sprite animation without using double buffering on 8 bit CPU, looks impossible? It cannot be double buffered as it needs at least 150KB of RAM but the MCU had just 2.5K! But I had to belive it as it was on Adafruit. I don’t know hows its happening, I mean how they achive such frame rates. Once I tried to interface 320×240 QVGA TFT with AVR, it was taking seconds to update the entire screen but “Microtouch” seems to update the screen @ several frames per second! Note: Images Copyright (C) www.adafruit.com