Internal Port Decoding b0-7 Register
From SpecNext Wiki
| Next Register Number | $82 |
|---|---|
| Readable | Yes |
| Writable | Yes |
| Short Description | Enabling internal ports decoding |
| Bit | Description |
|---|---|
| 7 | Enabling IO:$xx37 (also MD2 controller) |
| 6 | Enabling IO:$xx1F (also MD1 controller) |
| 5 | Enabling IO:$xx6B |
| 4 | Enabling +3 floating bus |
| 3 | Enabling IO:$1FFD |
| 2 | Enabling IO:$DFFD |
| 1 | Enabling IO:$7FFD |
| 0 | Enabling IO:$xxFF |
All bits are set to 1 upon soft reset.
(note: Next registers with number higher than $7F are inaccessible from Copper code)