DMA, memory to memory, memory to peripheral. (Kinetis and i.MX RT1020)

[luishs]

Hi.

I have some doubts about the handling of the DMA, I need to configure the DMA to send and receive data from/to the GPIO ports, using microcontrollers Kinetis and RT1020. The SDK examples are only for peripherals such as SPI, UART, I2C, I2S and for memory to memory, but there are none to receive/send data from/to GPIO ports.

In addition to preparing the transfer, I see that three configurations can be used, memory-memory, peripheral-memory and memory-peripheral.

EDMA_PrepareTransfer(&transferConfig, srcAddr, sizeof(srcAddr[0]), destAddr, sizeof(destAddr[0]),
                         sizeof(srcAddr[0]), sizeof(srcAddr), kEDMA_MemoryToMemory);

typedef enum _edma_transfer_type
{
    kEDMA_MemoryToMemory = 0x0U, / *! <Transfer from memory to memory * /
    kEDMA_PeripheralToMemory, / *! <Transfer from peripheral to memory * /
    kEDMA_MemoryToPeripheral, / *! <Transfer from memory to peripheral * /
} edma_transfer_type_t;

The question is whether I could use the DMA SDK examples for memory-to-memory transfers, replacing the source or destination address, with the GPIO port address, so that I can send or receive data, using DMA, from/to GPIO ports. . Although I still don't know how useful the parameter is that in the preparation it indicates the type of transfer.

[mjbcswitzerland]

Hi

If you use port addresses as source or destination pointers you can transfer to/from ports as any other peripheral.
If you search the forum you will find a number of posts where this is done, including Kinetis port change triggered transfers.

Regards

Mark

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[luishs]

Thanks Mark