Use SD card for save font and bitmap in codevision AVR

[meysam_abbasinia]

hi
in a project I'm working on 7 inch TFT LCD and ATXmega128A1, we need save font and icons on flash memory of AVR, now the memory is full and need more space so we decide use SD card for save fonts and icons on it in FAT format, but I don't know how can I use GLCD function by external memory.
for example we use glcd_putimagef for display an image from flash memory and compiler says we can use glcd_putimagex for display images from external memory, but how?

my ask is what should I do? I need save fonts on SD card. I need some sample.

thank you.

 

[Vbase]

This PIC project uses FAT32 SD to store bitmaps and display them on TFT, maybe you can get some ideas.
https://www.moty22.co.uk/sd_bmp.php

 

[meysam_abbasinia]

he try to read bitmap file directly, let me test it, read bitmap file and write to TFT lcd directly and I will say result.

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No, that is not good idea. thank you for your link

 

[ernpao]

I think that a 7 inch tft is too big for your mcu in terms of memory (RAM and not really program memory) as well as speed. You may be able to get away without using a RAM buffer on your mcu (but you will get 'flickering' as you draw on your screen) but I think using an sd card will slow down your system even further. I think the link vbase posted is ok, but your current mcu may just not be fast enough. In short, I think you should be using a more powerful mcu for driving a 7 inch lcd + sd card for memory, but that is just my 2 cents :-D