STM32x MDMA maximum Clock speed

[Rick Hamilton]

Posted on May 03, 2018 at 16:44

I have developed dozens of products using the STM32 Family, but can not find an easy solution for my latest requirement...

I need to collect fast A to D samples (from an external 8 bit A to D)... every 20ns.

Is it possible to use an 8 Bit parallel port and save 256 bytes into main memory using MDMA clocked using an external 50MHz source?

Thanks

Rick

[Tesla DeLorean]

Posted on May 03, 2018 at 19:35

For synchronous parallel input look at the camera interface DCMI. Should support rates north of 50 MHz. Also see FIFO devices.

Not really a DRQ/DACK model in STM32. You can use FSMC, or block of GPIO, and trigger DMA via TIM CHx input pin.

[Rick Hamilton]

Posted on May 04, 2018 at 07:13

Thanks Clive,

I did consider that but have no experience of using it.  I want to have a first hit production on this PCB so may get a development board in and try it, thanks.  Like you say I could supply the clock and also use it for the DMA Trigger.