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DGZ80 TRIVIA - Rare Optional Features - Printable Version

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DGZ80 TRIVIA - Rare Optional Features - someone - 29-11-2020

The DGZ80 offered Vectored Interrupt support using the AM9519 and Software Write Protect(SWP) using the 74S200 RAM.
These features are hardly used and most DGZ80s made do not have them installed.

Because the DGZ80 used a Z80 PIO and Z80 CTC it offered support for using the Z80's prioritised interrupt daisy chain signals.
It did however require the repurposing of some S100 pins.

By the time the DGZ80 was released the 74S200 was very expensive, essentially obsolete and extremely hard to source.
The SWP allowed 256 byte sized pages of system RAM to prevent the DGZ80 from writing to them effectively making them temporary ROM. It is not a feature often used by CP/M based disk systems.