Devices and expansion
Physical slot identity and the boundary of current driver support.
Device map
| Index | Device | Mountpoint | Driver and role |
|---|---|---|---|
| 0 | /dev/smp0 | /mnt/smp0 | SMP block driver; normally the protected boot ROM. |
| 1 | /dev/smp1 | /mnt/smp1 | SMP block driver; normally the writable data cartridge. |
| 2 | /dev/fd0 | /mnt/fd0 | Reserved, OFF; no floppy driver. |
| 3 | /dev/cf0 | /mnt/cf0 | Reserved, OFF; no CompactFlash/IDE driver. |
Boot-device mapping
The boot slot is marked read-only independently of whether it is SMP0 or SMP1. Its filesystem device exposes 32 logical sectors starting at physical sector 96, corresponding to EPROM offsets 0x6000–0x7FFF. The rest of the ROM contains the bootstrap, kernel, modules and resources.
The other SMP driver can address up to 256 logical 256-byte sectors, or 64 KiB. This driver bound is not an automatic capacity measurement. The mounted MKS2 header specifies a supported size, and formatting performs alias checks.
Console and null
CAT and CP implement the /dev/console and /dev/null stream cases themselves. These are not ordinary MKS2 files and are not accepted by the native regular-file OPEN service or BASIC OPEN.
CAT can echo console input until SU+D. CP can send a file to the console or null; it cannot capture an unknown-length console stream into a file.
Future XP1 support
The device abstraction carries a driver callback, physical unit, flags, a 32-bit logical capacity and a base LBA. This leaves room for later drivers without renaming the two physical SMP slots.
Version 0.6 does not include a PC16550, 16450, 68B50 or other UART driver, nor an XP1 bus probe. The UART command reports this state. A future expansion needs agreed hardware decoding and an implemented driver; the presence of a reserved name is not working hardware support.