Memory Controller
The Hornet memory controller block controls accesses to all system ROM/RAM and all
plug-in cards. It contains circuitry to provides a bank switching scheme which supports
one 64-KB bank and eight 16-KB banks. The memory controller also supports display
address remapping which allows address lines to be sourced from either the CPU or from
the display controller. In addition, it supports two I/O windows which provide I/O
address space mapping. Lastly, it contains a DRAM controller which supports up to four
32-MB banks of DRAM.