Help Needed in Building a Simple Project with STemWin and STM32CubeIDE

Hi @Imen DAHMEN​ 

Thank You for your response.

But maybe I am not very much clear in my last post.

As suggested by you, I am already using the "STemWin_HelloWorld" example from the CubeF7 MCU package.

And it works fine (also the project I created taking this as reference works fine).

I have two problems (this problem is also present in the STemWin_HelloWorld example.

• When I used single step debugging I can't see anything on the display, but if I pressed F8, I can see the text on the display.

void MainTask(void) {
 GUI_Clear();
 GUI_SetFont(&GUI_Font32_1);
 GUI_DispString("Hello World from STM32F7\r\n");
 GUI_DispStringAt("Hello world!", (LCD_GetXSize()-100)/2, (LCD_GetYSize()-20)/2); 
 while(1);
}

• When GUI_Delay is used, there is delay but nothing after the GUI_Delay Works. So Let's say, I used the below program and started debugging, and then pressed F8 to run the program freely.

void MainTask(void) {
 GUI_Clear();
 GUI_SetFont(&GUI_Font32_1);
 GUI_DispString("Hello World from STM32F7\r\n");
 GUI_Delay(1000);
 GUI_DispStringAt("Hello world!", (LCD_GetXSize()-100)/2, (LCD_GetYSize()-20)/2); 
 while(1);
}

I can see "Hello World from STM32F7" but not the "Hello World" on the middle of the screen. I have attached the picture also.

Right Side image is when I didn't used GUI_Delay and didn't use single step debugging.

Left side image is when I used GUI_Delay, GUI_Delay is doing it work can be seen from the below screenshot, my control is reaching the while(1), so it means GUI_Delay is not blocking the GUI_DispString function call.

Also regarding the points you mentioned that GUI_Init must be called and CRC should be enabled is already done. And since this is the example from CubeF7 package, I just modified it to include Delay and another Display String line.

Do you have some suggestions here now?

Thanks @Imen DAHMEN​ for your response.

I will answer your questions.

"Is it possible to check the display behavior when increasing the memory allocated to the GUI?

Note that if there is no enough memory to create the memory device, the performance of the display will be decreased."

I increased the memory and there is no effect at all, situation is still same, I did changes in GUIConf.c file, earlier the value was 256 and I changed to 400, but as mentioned situation is same.

#define GUI_NUMBYTES (400) * 1024
U32 aMemory[GUI_NUMBYTES / 4];

Did you try the Windows Manager?

I would say I tried but not whole heartedly, and when I tried it also doesn't work properly, maybe I can spent some more time on this but I am curious why a simple program with delay is not working. Earlier I was using the emWin windows simulator and I don't have any problem in the simulator window, GUI_Delay was working fine there, which means that this is supported by library and should also work on STM32F769I-DISCO board. Anyways I know that you guys will find the solution for me, many thanks for that.

GUI_Delay�? API calls internally “GUI_Exec�?. The call of “GUI_Exec�? regularly is recommended to update the modified windows.

“GUI_Exec�? API send notifications to STemWin callbacks and update all invalidated windows.

Thanks for detailed explanation, my understanding was that GUI_Delay uses GUI_X_Delay and GUI_Exec functions internally. And I will share one scenario with you.

Below is the program, where I wanted to display three Hello World message on the LCD Screen, and as I mentioned in the previous post that when I used GUI_Delay function, the emWin API which I use after the delay doesn't work.

So, in this case I just "Hello World-1" message on the screen (If I remove delay I get all three messages)

void MainTask(void) {
 GUI_Clear();
 GUI_SetFont(&GUI_Font32_1);
 GUI_DispString("Hello World-1\r\n");
 GUI_Delay(1000);
 GUI_DispString("Hello World-2\r\n");
 GUI_Delay(1000);
 GUI_DispString("Hello World-3\r\n");
 while(1)
 {
 GUI_Delay(100);
 }

Assuming that GUI_Delay(1000) is equals to GUI_X_Delay(1000) + GUI_Exec(), the above program can be breakdown as.

void MainTask(void) {
 GUI_Clear();
 GUI_SetFont(&GUI_Font32_1);
 GUI_DispString("Hello World-1\r\n");
 // GUI_Delay(1000);
 GUI_X_Delay(1000);
 GUI_Exec();
 GUI_DispString("Hello World-2\r\n");
 // GUI_Delay(1000);
 GUI_X_Delay(1000);
 GUI_Exec();
 GUI_DispString("Hello World-3\r\n");
 while(1)
 {
 GUI_Delay(100);
 }

but now I modified the program like below. Here I give a delay, and then used emWin API to display "Hello World-2" on display and then used GUI_Exec function.

void MainTask(void) {
 GUI_Clear();
 GUI_SetFont(&GUI_Font32_1);
 GUI_DispString("Hello World-1\r\n");
 GUI_X_Delay(1000);
 GUI_DispString("Hello World-2\r\n");
 GUI_Exec();
 GUI_X_Delay(1000);
 GUI_DispString("Hello World-3\r\n");
 GUI_Exec();
 while(1)
 {
 GUI_Delay(100);
 }

And in this case I get "Hello World-1" and after 1 second delay "Hello World-2" but no "Hello World-3"

This means that first call of GUI_Exec does it work, but after this it doesn't work. I don't know the reason, just sharing whatever I find here and did till now.

And my understanding is that, it might be due to the same reason when I do single step debugging I am not able to see anything on display.

Just to mention I am not the only one who faced this issue, some of the posts from the ST Community which are not yet solved.

STemWIn, GUI_DispString function isn't working after a while

I'm working on stm32f469 discovery board for GUI application , using stm32cubemx 5.4 and graphics framework stemWin, where I want to display integers from 1 to 5, my delay function is not working I guess, only 1st value 1 is displaying on the screen.

Why does not the LCD update in STM32H747I-DISCO board?

"I haven't tested the provided "STemWin_HelloWorld" example available in the CubeF7 MCU package, since I'm working from home, and I don't have access to that specific board, but that should work.

I will try to contact our STemWin expert internally for investigate more and answer your questions."

If possible for you, in case you have any other ST board with a LCD, you can test the HelloWorld program with the usage of GUI_Delay function, but if difficult for you, for me it's not a problem.

I will wait for some answer from your side after you get some inputs from STemWin experts team members.

Just to mention, since the subject of this post was different, I had created another post, but it's not an issue, you can still reply me here and once we get the solution I will update that post also.

STemWin_HelloWorld Example Debugging and GUI_Delay Not Working

Since this topic was urgent for me, I have created a Support ticket also with case number 00149151

And @Imen DAHMEN​  thanks a lot for supporting me with this issue I am facing.

Hi @Imen DAHMEN​ 

Did you get some information from your colleagues regarding the issue?

This is my last message and after this I will not follow-up, I have already communicated ST Support at various places and didn't get feedback. So I will not waste anyone's time.