STM32F4 and 1024x600 display refresh problem

nicola2 · ‎2015-06-30

Posted on June 30, 2015 at 16:02

Hello,

I'm using stemwin 5.26 on STM32F429IIT6 using LCD controller and freertos. my display is 1024 x 600. I started to implement some simple windows, but I see that refresh of the window causes a visible frame corruption. I made and attached a small video to explain clearly the issue.

I saw that using only on later (GUI_NUM_LAYERS 1) seems to cancel the issue. I cannot focus if the problem is in the ltdc configuration, dma2d config or STemWin libs.

Here code snippets of what I have in the program.

main()

{

/*** [.....] ****/

/* Initialize GUI */

GUI_Init();

osThreadDef(defaultTask, StartDefaultTask, osPriorityNormal, 0, 128);

defaultTaskHandle = osThreadCreate(osThread(defaultTask), NULL);

osThreadDef(GUI_Thread, GUIThread, osPriorityLow, 0, 20 * configMINIMAL_STACK_SIZE);

osThreadCreate(osThread(GUI_Thread), NULL);

/* Start scheduler */

osKernelStart();

}

/**************************************************************************************/

static void GUIThread(void const * argument)

{

GUI_SelectLayer(1);

GUI_SetColor (GUI_YELLOW);

GUI_FillRect(600,300,1024,600);

GUI_SetColor (GUI_BLUE);

GUI_FillRect(20,10,500,500);

k_InitMenu();

while(1)

{

LED_Toggle(LED1);

LED_Toggle(LED2);

GUI_Delay(100);

}

/**************************************************************************************/

void k_InitMenu(void)

{

WM_SetCallback(WM_HBKWIN, _cbBk);

GUI_SelectLayer(1);

WM_CreateWindowAsChild(0, 0, 1000, 25, WM_HBKWIN, WM_CF_SHOW | WM_CF_HASTRANS | WM_CF_MEMDEV, _cbStatus, 0);

}

/*******************************************************************************

* @brief Callback routine of desktop window status.

* @param pMsg: pointer to data structure of type WM_MESSAGE

* @retval None

*/

static void _cbStatus(WM_MESSAGE * pMsg)

{

int xSize, ySize;

static uint8_t TempStr[50];

static WM_HTIMER hTimerTime;

static uint8_t tmp;

static uint8_t bmp_res2;

RTC_TimeTypeDef RTC_Time;

RTC_DateTypeDef RTC_DateStructure;

uint8_t sec, min, hour, day, month;

uint16_t year;

WM_HWIN hWin;

hWin = pMsg->hWin;

switch (pMsg->MsgId)

{

case WM_CREATE:

hTimerTime = WM_CreateTimer(hWin, ID_TIMER_TIME, 1000, 0);

break;

case WM_DELETE:

WM_DeleteTimer(hTimerTime);

break;

case WM_TIMER:

if( WM_GetTimerId(pMsg->Data.v) == ID_TIMER_TIME)

{

WM_InvalidateWindow(pMsg->hWin);

WM_RestartTimer(pMsg->Data.v, 1000);

}

break;

case WM_PAINT:

xSize = WM_GetWindowSizeX(hWin);

ySize = WM_GetWindowSizeY(hWin);

/* Draw background */

GUI_Clear();

GUI_SetColor(0x008d00);

GUI_FillRect(0, 0, xSize , ySize - 3);

GUI_SetColor(0x808080);

GUI_DrawHLine(ySize - 2, 0, xSize );

GUI_SetColor(0x404040);

GUI_DrawHLine(ySize - 1, 0, xSize );

/* Draw time & Date */

GUI_SetTextMode(GUI_TM_TRANS);

GUI_SetColor(GUI_WHITE);

GUI_SetFont(GUI_FONT_13B_ASCII);

k_GetTime(&RTC_Time);

sec = RTC_Time.Seconds;

min = RTC_Time.Minutes;

hour = RTC_Time.Hours;

k_GetDate(&RTC_DateStructure);

sprintf((char *)TempStr, ''%02d:%02d:%02d'', hour , min, sec);

GUI_DispStringAt((char *)TempStr, xSize - 70, 4);

year = RTC_DateStructure.Year + 2014;

month = RTC_DateStructure.Month;

day = RTC_DateStructure.Date;

if((day > 0) && (day <= 31) && (month > 0)&& (month <= 12) && (year >= 1900))

{sprintf((char *)TempStr, ''%02d, %s, %04d'', day , strMonth[month-1], year);}

else

{sprintf((char *)TempStr, ''01, January, 2014'');}

GUI_DispStringHCenterAt((char *)TempStr, xSize / 2, 4);

GUI_DispStringAt( (char *)TempStr, 50, 4);

break;

default:

WM_DefaultProc(pMsg);

break;

}

#display-stm32f4-lcd

nicola2 · ‎2015-07-07

Posted on July 07, 2015 at 11:15

After few attempts, I found that reducing the speed of LTDC peripheral can cancel the problem.

My 1024x600 display can support higher clock and the LVDS converted the same. I have to decrease to 20 MHz instead of 32 MHz. Is there some limits I have to consider?

Best Regards