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Two thirds of this article is about generic ISA DMA programming. That part of it does not belong in the "Storage" category at all. One third of it is about DMA Floppy Driver programming. This very much belongs where it is. The article desperately needs to be busted into two pieces. ISA DMA programming goes somewhere else (and NOT just named "DMA" either!). The remaining article links to the ISA DMA article, and gets renamed "Floppy DMA", I think. And the Genesis thing is amusing, but certainly overdone. And it makes baby Brynet cry. Bewing 03:01, 23 March 2008 (CDT)

Actually, I'd like to see a split into three parts: DMA (theory), PC DMA, Floppy Programming. Doing so would make a complete series on the matter (what is dma, how does it work, and how you can use it). Unfortunately, there's little in this article to provide the first. A stub is however easily made. (and I don't mind adding a bit of common sense to it when I get the time.). WRT Genesis, I kinda like it (and who cares about what brynet thinks anyway `o.o´) - Combuster 04:10, 25 March 2008 (CDT)
On that topic, I feel as if this article does more bashing than adding actual information. Yes we get it, DMA sucks and should be dead and buried, but do we have to beat it down with a shovel? Primis 19:35, 29 December 2011 (EST)
Actually DMA is still alive. ISA is what has been bashed on time and time again and yet it's kept on life support for an equal period of time. Any specific points of improvement you are suggesting (other than that the DMA theory page is still missing) - Combuster 11:46, 30 December 2011 (UTC)
I think that, at the very least, we should write some example code in C, Organize the information better. I also think we should have more information about busmastering DMA, since, this article is about DMA, not just ISA. - Primis 16:00, 31 December 2011 (EST)


This page could use a rewrite. -Mystran 2007-04-02

I definitely agree that it needs a lot of work. I really dislike, among other things, the "DMA Genesis" section. That said, I think it's better to improve (3rd person, more informative, to the point) the current article until it meets expectations than to restart it. The "Floppy Disk DMA Programming" could be very helpful (I have seen endless forum posts asking for help on floppy drivers). This section should be cleaned up, written in C and possibly split into another article. -Jhawthorn 21:27, 2 April 2007 (CDT)

I've added the following to what was orignally here, some of it has been re-written a great deal of it has been written from personal experience at swearing at the little DMA chip or it's functional equivalent. Still more to come, there's a lot of thoery to understand before simply writing code. The DMA chip has a lot of 'interesting' and 'unexpected' features. Failing to take these into acount will result in nothing working. You have been warned :-). XARDFIR

Actual 8237 information

I don't know if you've ever thumbed through the 8237 datasheet, but I wanted to point out, the IBM implementation of the chip is only missing one signal, /EOP. This technically can interrupt the processor upon DMA completion. There are no other signals on this chip not brought out on the ISA bus.

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