Port configuration driver register
| HDRV0 | Port hdrv bit 0 |
| HDRV1 | Port hdrv bit 1 |
| HDRV2 | Port hdrv bit 2 |
| HDRV3 | Port hdrv bit 3 |
| HDRV4 | Port hdrv bit 4 |
| HDRV5 | Port hdrv bit 5 |
| HDRV6 | Port hdrv bit 6 |
| HDRV7 | Port hdrv bit 7 |
| HDRV8 | Port hdrv bit 8 |
| HDRV9 | Port hdrv bit 9 |
| HDRV10 | Port hdrv bit 10 |
| HDRV11 | Port hdrv bit 11 |
| HDRV12 | Port hdrv bit 12 |
| HDRV13 | Port hdrv bit 13 |
| HDRV14 | Port hdrv bit 14 |
| HDRV15 | Port hdrv bit 15 |