Changes
The IDE8255 is supported by [[FutureOS|FutureOS]].
== I/O Ports ==
Each of the I/O ports is (intentionally) mirrored to four addresses:
F8E6h,FAE6h,FCE6h,FEE6h PIO 8255 Port A (8bit data) ;\together
F9E6h,FBE6h,FDE6h,FFE6h PIO 8255 Port B (8bit data) ;/16bit
F8E7h,FAE7h,FCE7h,FEE7h PIO 8255 Port C
F9E7h,FBE7h,FDE7h,FFE7h PIO 8255 RS
The distance between the Port A / Port B address mirros is 100h bytes. This allows to read 8 bytes (aka four 16bit words) at very fast speed, by using a sequence of INI opcodes (which read from address BC, and decrement B).
== Images ==
