Dear emWin-users,

I am trying to draw a Bitmap picture (abc.bmp) from an external sd-card on the LCD with the GUI_BMP_DrawEx()-function.
So I have stored a .bmp file on my external sd-card and do the following: here is my code:

/////////////////
FATFS FatFs;
FRESULT res;
FIL fil;


static char _acBuffer[400];

int APP_GetData(void * p, const U8 * * ppData, unsigned NumBytesReq, U32 Off) {
FILE *phfile;
DWORD NumBytesRead;
phfile = (FILE *)p;

//
// Set file pointer to the offset location
//
fseek(phfile, Off, SEEK_SET);
//
// Read data into buffer
//
NumBytesRead = fread(_acBuffer, sizeof(char), NumBytesReq, phfile);
//
// Set data pointer to the beginning of the buffer
//
*ppData = _acBuffer;
//
// Return number of available bytes
//
return NumBytesRead;
}


int main (void)
{

res = f_mount(&FatFs, " ", 1) // it passes, it is successfully mounted (FR_OK after debugging);

res = f_open(&fil, "abc.bmp", FA_CREATE_ALWAYS | FA_WRITE); // it passes, it is successfully opened (FR_OK after debugging)

GUI_BMP_DrawEx(APP_GetData, fil, 0, 0);

}

But somehow nothing happens ..... it is not visualized on the screen....

Can you help me or provide a small example.....

Thanks
Ivo

Hi Sven,


thank you for you continuous support here....

So today I was able to reproduce a *.bmp file on my screen, but only with a restricted size. For example, a picture of appr. 350x200 pixels I can display well, but a 600x200 I cannot (my external display is 800x480).
After break pointing in the APP_GetData() --> NumBytesRead for the 350x200-bitmap is 1096 and since my _acBuffer is [1200] all works fine.... I increase the buffer to _acBuffer[5000] but it still cannot reproduce 600x200 picture from an external sd-card.

Any idea....??

I am using an external SDRAM and I edited GUIConf.c like following (and it works, obviously I can display at least some pictures from external sd-card):

#define GUI_NUMBYTES (1024) * 120 ---> what about this ??


#define GUI_BUFFER_IN_EXT_RAM 1
#define GUI_BUFFER_ADDRESS 0xD0600000
#define OS_SUPPORT 1



void GUI_X_Config(void) {

//
// 32 bit aligned memory area
//
#ifdef GUI_BUFFER_IN_EXT_RAM
static U32 aMemory[GUI_NUMBYTES / 4]__attribute__((at(GUI_BUFFER_ADDRESS)));
#else
static U32 aMemory[GUI_NUMBYTES / 4];
#endif
//
// Assign memory to emWin
//
GUI_ALLOC_AssignMemory(aMemory, GUI_NUMBYTES);
//
// Set default font
//
GUI_SetDefaultFont(GUI_FONT_6X8);
}



Thank you