DMA clock frequency

[Alexandre T]

Posted on October 23, 2017 at 11:54

Hello,

Is it possible to change the DMA clock frequency ? 

If so, how to do that ?

(STM32L071)

[Alexandre T]

Posted on October 24, 2017 at 17:02

No idea ?

[Tesla DeLorean]

Posted on October 24, 2017 at 17:14

To what, from what? The DMA clock comes from the AHB/APB.

You can use a TIM to trigger DMA transfers, and set that to whatever rates the TIM affords.

[Alexandre T]

Posted on October 24, 2017 at 17:21

Yep I know that it comes from the AHB/APB.

I'm using the DMA to collect accelerometer datas.

The problem is that the DMA speed is faster than my accelerometer refresh rate and I want to avoid memory waste.

So, the goal is changing the DMA clock frequency is to adapt it to my accelerometer frequency.

[Tesla DeLorean]

Posted on October 24, 2017 at 17:29

It is generally undesirable to throttle the bus clocks as this will slow the entire system down and increase bus contention and delays.

Pace the acquisition of data from the accelerometer with a TIM