What is DMA? What does it do? and Why is it Important?

In a previous video I mentioned DMA, so in this video we're going to learn what it is, how it works, and why it's so important.

Before DMA we had PIO (Programmed Input/Output) mode, meaning the reading and writing was all done via the CPU. DMA (Direct Memory Access) speeds things up a little and usage dates back to some of the very early computers including the Atari 7800, C64 and more. Don't worry, you don't need any programming knowledge to understand this, it's quite straight forward, but I hope by the end of the video you'll have a good understanding of it.
I also cover my experiences at college learning to program in Turbo Pascal and programming the Sound Blaster 16 to play MOD files in MSDOS. Does something like this "SET BLASTER=A220 I7 D0 H5 T6" bring back any memories?

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Chapters:
Introduction (00:00)
Before DMA (00:19)
DMA (Direct Memory Access) (03:11)
3rd Party DMA (03:37)
1st Party (Bus Mastering) DMA (04:01)
Burst Mode (04:47)
Cycle Steeling Mode (05:02)
Transparent Mode (05:29)
Interleaved Mode (Amiga) (05:44)
My Turbo Pascal MOD Player at College (06:18)
PC Games Programmers Encylopedia (PCGPE) (06:43)
The Sound Blaster 16 DMA (07:12)
No More DMA (07:55)

Music:
Automater by Netrunner of Count Zero / KMC
Internal Sounds by Pepito/Playmobil
Raven Allnite! by Brett Mitchell for Amiga Format

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#dma #computerscience #howitworks