stm32f4 tft lcd example pricelist

Ahh yeah look at that! If you look closely, top right of the LCD, that’s obviously a flex connector for a resistive touch overlay (4 contacts running to the 4 sides of the LCD overlay).

Agreed! I will be picking one up. I’ve been happy developing for the stm32f4discovery (and other stm32 chips) with gcc, openocd and gdb. It is all free.

The STM32F4 cores are pretty well supported by libopencm3 and Code Sourcery and summon-arm-toolchain both build working toolchains and openOCD supports the stlink natively now.

A fair number of inexpensive baseboards/motherboards/accessories have also appeared for earlier versions. I hope Olimex puts out a couple nice STM32F429/427 boards.

I can see there is only a STLINK usb connector on board, so there is even no FS to expect. beside HS, I suppose does mean High Speed (480mbps). but HS anyway needs a separate physical layer USB chip for addition to STM32F4 chip and most likely this is chip is not present on this board anyway, because this is STM32F4+LCD+SDRAM demoboard and there is no need for USB at all.

The data brief bullet-points “USB OTG with micro-AB connector”. Looks like the micro-usb is on the underside, sticking out at the bottom of the photo. With matching T/H mounting tabs on the topside, labelled USB USER. But like you said, the STM32F4 requires an external PHY for HS, and it seems unlikely they’d include one on this board.

I think Farnell’s 21€ will be accurate, as ST’s suggested USD price is $24. The placeholders for the STM32F429I-DISCO on element14 (a division of Farnell) and mouser show $42, which I think predates the later ST announcement. I think the ST announced $24 will hold, and the distributor prices will match that, as they have in the past.

I wouldn’t expect TI to hack profits from their calculator range, and HP have always been expensive, but ST could easily change their format to calculator-friendly. Clamshell design, LCD & battery in top half, CPU & keypad in bottom half, expansion pins to left / right of keypad makes a self contained unit.

HP Palm – Love the idea, hate the baguette (french bread loaf) layout. If I could get custom key covers, and surface-mount key switches, I’d be designing my own low-profile keypad to go with an LCD module. Top side keypad, bottom side CPU / RAM / USB / LCD driver / power regulation / expansion port.

Great find, thanks! Man, could they have buried the details on that guy any farther down into the document? I can’t help but feel like a quick pointer in the LCD section to “oh by the way there’s a touch screen, here’s how to talk to it” would have been a good idea.

It’s certainly useable in any other project where you have an onboard LCD controller. Especially any other project that happens to use a STM32F4. What difference would it have made if it had an external controller? Surely it’d have been on the same PCB. Were you hoping for a removeable SPI-interfaced module?

Look in the UM1670 user manual, paragraph 4.8: the tft includes an ILI9341 controller. The ILI9341 has it’s own graphics ram inside, it is not mapped into the STM32 address space. It is connected to the STM32 via a parallel bus. The ILI9341 and similar controllers are common on cheap chinese tfts. So it is no problem to source similar tfts for your final product after developing on the discovery board.

UM1670 in paragraph 4.8 also says that “The TFT LCD is a 2.41″ display of 262 K colors. Its definition is QVGA (240 x 320 dots) and is directly driven by the STM32F429ZIT6 using the RGB protocol”. ILI9341 has multiple modes of operation including direct RGB/HSYNC/VSYNC mode which bypasses internal GRAM. I don’t have the board yet but I assume display buffer is located in external SDRAM which is also on the board. The whole point of this kit is to show TFT and SDRAM interface in new STM32F4x9.

I’ve checked this discovery board firmware available from ST’s site (“STM32F429 discovery firmware package UM1662” number: STSW-STM32138, btw. finding it is a bit difficult – ST’s site is terrible):

They are using FreeRTOS, FatFs, STemWinLibrary which is ST’s version of Segger’s emWin graphic library and STM32F4xx_StdPeriph_Driver v1.2.1 which includes F429/439 support (FMC, LTDC and DMA2D added).

Check again martin. Those lines have pullups to vdd and are connected to cpu pins. I have this board for some time and I can confirm that lcd is driven by lcd controller from cpu and frame buffer is in external dram which is also on the board.

You can refer to the examples under STM32CubeF4 package to see their structure and get inspired from them to configure your files: STM32Cube_FW_F4_V1.21.0\Projects\STM32F429I-Discovery\Applications\STemWin

STM32F429 has also LTDC driver for LCD like that, but this driver we will use later. For now we will use SPI for driving in serial mode and some other pins for controlling.

Remember: This library can also be used, if you are not using STM32F429 Discovery. It can be used in previous STM32F4 Discovery board. All pins can be changed in defines.h file which is included in project.

This tutorial shows you how to display string, color and dynamic value on LCD with STM32-Nucleo development board from ground up. It will also show you how to read the technical datasheet of LCD. If you are interested in more advance topic of RTOS from scratch, please go to Real-Time Operating Systems tutorial.

You can think of it as a tiny and simplify PC without monitor(output), keyboard(input), and mouse(input). The LCD acts as output and the Potentiometer acts as input in our tutorial. There is a big problem, how can this tiny PC communicate with the outside world (such as monitor or keyboard)? Some use wired or wireless.

In this tutorial, we will use SPI (Serial Peripheral Interface) to communicate with the output device ~ LCD. We call our Nucleo board as master and the LCD as slave because we are sending order and command to the LCD. Sparkfun has a great tutorial website about SPI (link). The image in the following shows the relationship and connection between master and slave.(image from Sparkfun with some modification to fit our case)

We want to display some string or color on the specific location of the LCD. We can achieve this by sending data to the specific address of RAM (Memory) in the LCD board. This is call Memory to Display Address Mapping. Take the image below for example. We want to make the top left corner of the LCD display a yellow square. First, you need to let the LCD knows at where of the RAM are you going to write the data to (using X_start, X_end, Y_start, Y_end value). Then you can start writing the data (color information) to those address of the RAM. Then, the specified portion of LCD will change it"s color according to the value you wirte into the address in the RAM. (Please refer to the ST7735s datasheet page 59 ~ 72)

We will talk about how to connect these two devices by wires later. Let"s see the protocol when communicating to the LCD board. First look at the graphic explanation below.

Command: You use the low voltage from the GPIO pin to tell the LCD board that you are transmitting the command. (Please refer to the ST7735s datasheet page 36 ~ 51)

Click File --> New Project --> In the search, key in your board model (STM32f411RE in our case) --> Click on the NUCLEO-F411RE --> Double click the item --> Click Yes to initialize all peripherals with their default Mode. --> Clear all Pinout.

You may wonder what pin of SPI should I use (you see we change the pin from the default PA5~7). Actually, ARM Cortex-M4 defined the combination of pins with SPI, I2C, UART. You can check the table from the STM32F411RE User Manual page 47 ~ 52. In the table, you can see we are using the combination of PB3/PB5, that combination also legit.

After you connect these devices, connect USB with the PC and Nucleo-64 board. Your PC should be able to detect the Nucleo board and the LED light near the Mini usb port should be steady red ligh. The LCD should be power on with white screen.

In the main function will be like the following. We read the value from the ADC (Analog to Digital Conversion) and this value would change if you tune the potentiometer. The plotData function will take this value and plot it on the LCD.

Before starting to display anything on the LCD, we need to initialize and configure the LCD by sending some command and parameters (data) to the LCD board. This initialization only need to be processed once. After that, we can send data to the LCD with correct protocol.

Let"s make the uper left corner of the LCD become green. In the following sending command as well as sending data, we all communicate via SPI. Remember that before sending data, we need to set the RS (Data or command) pin high. We set the RS pin low before sending command.

The reason of making this tutorial is that the code provided from instructor of the Udemy course is not working at all and the instructor didn"t reply to any student at all. I start from knowing nothing about SPI no need to say the LCD board. After 5 days of research, reading documentation, and trial and error, I finally make it works. This tutorial is to guide those people who want to get a deep knowledge of making a driver to display on LCD.