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I’m trying to understand the ins and outs of how a DMA controller functions.
I’m looking at the 8237 DMA controller. Some information here has some tables with register values.
Are those the DMA’s own registers, or are they the CPU’s registers?
The DMA controller registers are distinct from the CPU registers (in the case of the 8237, it’s physically a different chip with different silicon). When programming, you can access the DMA controller registers using CPU
INandOUTinstructions as described on the page you linked (that’s the “I/O Port” column).A different hardware architecture may provide a different method of accessing a DMA controller registers, for example they could be “memory-mapped” instead of I/O ports.