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=== Input / Output ===
[[Input/output | I/O]] in the M65 is decoded into a 16 KB space to simplify the hardware. In fact the 1 KB of [[RAM]] is mirrored through the bottom 32 KB, the [[Input/output | I/O]] through the next 16 KB, and the [[EPROM]] through the top 16 KB. If you added an expansion board (see TANEX below) the decoding was modified and the wasted space reclaimed.
In common with other [[6502]] designs, [[Input/output | I/O]] is mapped into the memory space. There is no dedicated [[Input/output | I/O]] space as on the [[Z80]], [[8086]] etc. The [[Input/output | I/O]] ports are (when fully decoded):
*Write to $BFF0 Clear Keyboard Flag (Keyboard would generate an [[IRQ]])
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