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Address	Port Size	Signal	Description
11xx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx	32	kseg2 1023MB	Kernel cached tasks
10xx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx	32	kuseg 1024MB
01xx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx	32	kuseg 1024MB
001x:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx	N/A		Inaccessible 512MB
0001:1111:11xx:xxxx:xxxx:xxxx:xxxx:xxxx	8		Kernel Boot and I/O
0001:1111:1100:0xxx:xxxx:xxxx:xxxx:xxxx	8	/ROMSEL	Boot ROM up to 512K
0001:1111:1111:1xxx:xxxx:xxxx:xxxx:xxxx	8
0001:1111:1111:1111:1111:1111:1111:xxxx	8	/REGSEL	Onboard I/O port registers
0001:1111:1111:1111:1111:1111:1110:xxxx	8	/SCCSEL	Philips 2681+ DUART
0001:10xx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx	8	/IO8SEL	8-bit I/O space
0001:01xx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx	16	/IO16SEL	16-bit I/O space
0001:00xx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx	32		32-bit I/O space
0000:11xx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx	32		64MB Remap Window
0000:10xx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx	32
0000:01xx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx	32
0000:00xx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx	32		SRAM 64MB starting at 0x00000000

GAL Address Decoding and Select Line Generation

The master address decoder (MAD) shall be implemented in a 22V10 programmable logic device.
Select line outputs are configured as inverting so they will go high on asynchronous reset.
Address lines are not yet metastable on ALE↑. Decoding logic may proceed ungated, with select output flip-flops clocked on next SysClk↓ following ALE↑.
One FF feeds back to enable all select line outputs.
/Last high input while /OE enable is low provides the internal asynchronous preset.
A31:A26 are fully decoded to match 64MB regions.

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