XR88C681CP Datasheet, PDF (29/99 Pages) Exar Corporation – CMOS DUAL CHANNEL UART (DUART)

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Figure 7. Circuit Schematic depicting approach to Interface the XR88C681 DUART
to the 8080A CPU, for “External” Vectored Interrupt Processing
(Interrupt Service Routine resides at 0020₁₆ in Memory)
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