Bernie@GabeMoralesVR The A3000 RTC circuitry has a 4-bit data bus and 16 addressable registers. The CPU can directly read/write any of them, but there are no interrupts and no DMA.
The official PCB schematics are here:
https://www.amigawiki.org/doku.php?id=en:service:schematics
I've been using KiCad to view the gerbers, but the schematic diagrams seem to have some mistakes so I don't trust them.
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