Problem: how get data of DCMI and stored in other memory (flash ic & sd card & etc.) without stored full data in internal sram?

[kshin.111]

hi everyone i use stm32f407vg, camera ov7725(equal with ov7670) and spi flash ic w25q128.

now program working with HAl DCMI DMA for get data RGB565 of ov7725 and stored in sram and show in tft lcd but need to large memory.

add spi flash ic for stored.

Problem:

how get data of DCMI and stored in other memory (flash ic & sd card & etc.) without stored full data in internal sram?

[Tesla DeLorean]

Use methods​ where you can write data faster than it is coming in, and then flush half the buffer at each DMA HT and TC interrupts.

[kshin.111]

 thanks Clive Two.Zero

internal sram in stm32f407 not problem for first half buffer for image data but not space for second half!!!

i now get data of camera and in half transfer(HT) interrupt stored in other spi ic flash but:

 in HT interrupt dma i can't find way for change buffer save address.(for start again of first home buffer for second half data).

[Tesla DeLorean]

In the context I imagined the DMA buffer size was determined by available space rather than related to whole frames size.

For a 32KB DMA buffer in circular mode you'd need to flush 16 KB at each call.