IBM System/23 Datamaster: Difference between revisions
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=== Simplified Memory Map ===
[[File:IBM System-23 Simplified memory map.png|frameless|
The IBM System/23 divides its 64KB of addressable space in four segments of 16KB each. All even segments are fixed into the memory map but all the odds are paged and can support up to 16 pages each. The first half portion of the map corresponds to ROM while the last half of it is mapped to RAM.
Pagination is achieved thanks to four registers. From those, two determine where the CPU shall access its resources while the other two are reserved to the same purpose but only for DMA address generation. The widths of each register is four bits, therefore allowing the maximum of sixteen pages.
Video memory seems to be paged at address 8000h (to be confirmed).
== Units in collection ==
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