Is it possible to read from SD card into Arduino's Flash memory

Projects General Guidance
1
  • I'm trying to display images on an oled (0.96" monochrome, 128X64)
  • I've done it using examples where you program them directly on flash memory like this:
static const unsigned char PROGMEM image_array[] = { 
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, ...
  • However my goal is to display many different images, but only several fit in flash, even with Mega
  • So I got myself an SD card module thinking it should be easy to read from it and display

After searching a lot it seems like this is not easy at all, probably because the RAM is too small. So my question is whether it's possible to read a file from the SD card and store it on the Arduino's flash memory? The idea is to display it from there (using the Adafruit_SSD1306 lib), then replace it with a new image from the SD card and repeat?

2

Why not just read the multiple images directly from the SD card ?

3

Which "Arduino"? There are some 20 of them?

5

So read from SD card to RAM and then display? I've seen people struggling with this because the RAM is so small.

6

Depending ng and n exactly how you’re handling the Images, you could copy them directly to the display buffer.

Or, it might just necessary to buy a more powerful processor with more RAM.

7

I have an Arduino Uno R3 and Arduino Mega R3

8

For most practical purposes, no.
Only the bootloader can write to flash memory on an AVR. A sufficiently advanced ("larger") bootloader COULD read information from an SD card and put it in flash, but that's probably not what you want to do.

9

No.

10

@Railroader