Hercules microcontrollers, DMA and Memory Cache

RE: Hercules microcontrollers, DMA and Memory Cache

Naveen_R — Tue, 22 Apr 2025 06:27:33 GMT

Hi,
Thanks for this blog, where I found a clear-cut explanation on Cache coherence with DMA.

I could not be able to find the link for 4b which is a continuation of this blog, can you please share that link.

Kind Regards,
Naveen

RE: Hercules microcontrollers, DMA and Memory Cache

DAB — Sun, 03 Jan 2016 19:42:54 GMT

Great post Jan.

DMA can be very useful, but I want to make sure that everyone understands that DMA works by stealing CPU cycles.

Each DMA action will slow down your normal algorithm processing. Usually by a small amount, but if you use a lot of DMA, it can add up to be a significant affect on your timing budgets.

DAB

RE: Hercules microcontrollers, DMA and Memory Cache

clem57 — Sat, 02 Jan 2016 23:29:39 GMT

Thank you on describing cache coherence with DMA. This is a common occurrence since the microcontroller own's cache resource on the chip and not the external DMA circuits which can only see RAM.

Clem