wiki:nightowl:addressing
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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 | Boot ROM up to 512K | |
| 0001:1111:1111:1xxx:xxxx:xxxx:xxxx:xxxx | 8 | ||
| 0001:1111:1111:1111:1111:1111:1111:xxxx | 8 | Onboard I/O port registers | |
| 0001:1111:1111:1111:1111:1111:1110:xxxx | 8 | Philips 2681+ DUART | |
| 0001:10xx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx | |||
| 0001:01xx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx | |||
| 0001:00xx:xxxx:xxxx:xxxx:xxxx:xxxx:xxxx | |||
| 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
- 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.
- The clock input is driven by ALE↑ to latch the generated select line states into the output FFs.
- 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.
wiki/nightowl/addressing.1533764836.txt.gz · Last modified: 2018/08/08 17:47 by gtfjt
