[dottedmag]

Author here. Your guess is right.

A lot of hardware has migrated from using I/O ports to memory-mapped I/O, and instead of fixed I/O addresses ACPI or a similar mechanism provides the OS with the directory of memory addresses to talk to.

For example, instead of PS/2 keyboard/mouse at I/O ports 0x0060-0x0064, ACPI provides the OS with the memory address to talk to a USB controller, and the USB controller does not use I/O ports at all.

Have a look at a list of the most common I/O ports: https://wiki.osdev.org/I/O_Ports#The_list

Most of this hardware is gone. The easiest way to see them at all is to boot a VM in QEMU and specifically ask for these ancient devices to be present.

[mixmastamyk]

Yeah, I remember them. Never really understood what they did besides needing to be set for ISA cards, etc.