Hi,
Is it possible to use DMA with I2C with low CPU overhead?
Thanks,
Ahmad
DMA with I2C LPC17xx
Started by ●December 10, 2011
Reply by ●December 10, 20112011-12-10
Il 10/12/2011 20:58, ahmad alsaleem ha scritto:
>
>
> Hi,
>
> Is it possible to use DMA with I2C with low CPU overhead?
>
As I know it isn't possible on LPC17xx mcu family basically because you
need a peripheral to memory DMA transfer (in both directions of course)
and I2C it isn't in the list of peripherals that can request a DMA
connection. I used other mcus that have this feature but it isn't very
useful because DMA transfer can be triggered only by data reception or
transmission and all arbitration (start bit, address and so on) have to
be under mcu direct control. I2C flow control is quite complex so I
personally don't know an mcu that can leave all the I2C transmission or
reception management to a DMA. You can obtain a very good management
using interrupts.
> Thanks,
>
> Ahmad
>
>
>
>
> Hi,
>
> Is it possible to use DMA with I2C with low CPU overhead?
>
As I know it isn't possible on LPC17xx mcu family basically because you
need a peripheral to memory DMA transfer (in both directions of course)
and I2C it isn't in the list of peripherals that can request a DMA
connection. I used other mcus that have this feature but it isn't very
useful because DMA transfer can be triggered only by data reception or
transmission and all arbitration (start bit, address and so on) have to
be under mcu direct control. I2C flow control is quite complex so I
personally don't know an mcu that can leave all the I2C transmission or
reception management to a DMA. You can obtain a very good management
using interrupts.
> Thanks,
>
> Ahmad
>
>
