HD6433937 Datasheet, PDF (505/521 Pages) Hitachi Semiconductor – Hardware Manual

C.4 Block Diagrams of Port 4
FLEX^TM Decoder
READY
PMR4₃
IRQ₀
PMR4: Port mode register 4
RES
Figure C.4 (a) Port 4 Block Diagram (Pin P4₃) [Chip Internal Input Port]
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