bootload¶

install an OS image into the boot sectors
NAME
    bootload - install an OS image into the boot sectors

SYNOPSIS
    bootload file

DESCRIPTION
    Copies `file` (an assembled OS image, e.g. one just built under /src/os-bios)
    into the disk's OS region -- sector LBA 1 onward, where the ROM monitor's B
    command loads the OS -- and records its sector count in the boot block
    (OSCNT). The next time you `exit` to the monitor and press B, that image
    boots. bootload is a shell built-in.

    The running OS lives in RAM, so overwriting the on-disk OS region under it is
    safe. bootload writes the current drive (drive 0 is the boot disk). The image
    may be up to 32 sectors (16 KB).

    Typical self-hosting loop, rebuilding the OS on the machine:

        cd /src/os-bios
        make os                       assemble asm/p8xos.asm -> asm/bin/p8xos.bin
        bootload asm/bin/p8xos.bin    install it as the boot OS
        exit                          back to the monitor
        B                             boot the freshly built OS

THE MONITOR
    Only the OS is on disk. The MONITOR is EEPROM/ROM firmware -- it is what runs
    at reset and loads the OS -- so it cannot be installed from disk. To change
    the monitor you must reprogram the EEPROM (host-side: rebuild eeprom.bin and
    reflash the chip). bootload does not touch it.

SEE ALSO
    make, asm, save, exit