The Mark 1 BIOS is the deepest layer of the Mark 1's software hierarchy. The BIOS provides the core functionality of the computer, such as emulating power states, handling peripheral connections, managing the script control interface (SCI), initializing the computer during its boot sequence, and triggering the bootloader to launch the operating system, typically SCOPE.
The BIOS can be upgraded or repaired using a special BIOS utility tool, which modifies the BIOS ROM while the computer is turned off. This allows a computer with a corrupted BIOS to be repaired for data recovery.
The standard BIOS provided in the Mark 1 is the Leading Edge BIOS (or LE-BIOS), a reference to the now-defunct Leading Edge Products, which was popularized through sponsorship of early Computer Chronicles episodes that heavily inspired the development of the Mark 1.
All system calls in the Mark 1 Documentation that begin with "BIOS_" are BIOS system calls.
A complete list of BIOS system calls is available.
A BIOS fault occurs when the BIOS receives a system call that it does not support. Any link message that starts with "BIOS_" and is not supported by that BIOS version will cause a BIOS fault.
The BIOS fault screen has a red background and white text, and will show the command that caused the error. The only way to recover from a BIOS fault is to reboot.
BIOS faults are usually caused by typos. In the event that a future BIOS version adds a command that is unsupported by the installed version, any software which uses that command will crash the computer. When software is installed, it should check the BIOS version to ensure compatibility.
Unlike SCOPE errors, BIOS faults cannot be bypassed. They cause the system to hang, and it must be restarted. As soon as a BIOS fault occurs, all software is stopped and the BIOS drivers assume control. Any unsaved data is lost.
OLD LIST, TO BE REMOVED:
| Category | Command | Description |
|---|---|---|
| Disk | BIOS_DISK_CREATE_DIR |
Creates a directory. |
| Disk | BIOS_DISK_CREATE_FILE |
Creates a file. |
| Disk | BIOS_DISK_CREATE_STUB |
Creates a script stub file. |
| Disk | BIOS_DISK_DELETE_DIR |
Deletes a directory. |
| Disk | BIOS_DISK_DELETE_FILE |
Deletes a file. |
| Disk | BIOS_DISK_FORMAT |
Formats a disk. |
| Disk | BIOS_DISK_INFO |
Requests information about a disk. |
| Disk | BIOS_DISK_LABEL |
Changes the disk label. |
| Disk | BIOS_DISK_MOVE_DIR |
Moves or copies a directory. |
| Disk | BIOS_DISK_MOVE_FILE |
Moves or copies a file. |
| Disk | BIOS_DISK_READ_DIR |
Gets a list of files in a directory. |
| Disk | BIOS_DISK_READ_FILE |
Reads a file. |
| Disk | BIOS_DISK_RENAME_DIR |
Renames a directory. |
| Disk | BIOS_DISK_RENAME_FILE |
Renames a file. |
| Disk | BIOS_DISK_RUN_FILE |
Runs a file, if it is a script stub. |
| Display | BIOS_DISP_BACKGROUND |
Sets a background layer. |
| Display | BIOS_DISP_FOREGROUND |
Sets a foreground layer. |
| Display | BIOS_DISP_FONT |
Sets the font page. Only works on color monitors. |
| Display | BIOS_DISP_FULL |
Sets the entire display. |
| Display | BIOS_DISP_HOLD |
Hold display updates until BIOS_DISP_RELEASE. |
| Display | BIOS_DISP_INFO_REQ |
Requests info about the display (see BIOS_DISP_INFO_SEND). |
| Display | BIOS_DISP_PRELOAD |
Sets a preload layer. |
| Display | BIOS_DISP_RELEASE |
Releases display for updates from commands since BIOS_DISP_HOLD. |
| Display | BIOS_DISP_RESET |
Resets display. |
| Display | BIOS_DISP_SET |
Set characters on the display. |
| Display | BIOS_DISP_SET_FAST |
Set characters on the display temporarily. Faster than BIOS_DISP_SET, but will overwrite any dialogs or checkboxes. |
| General | BIOS_GETUSER |
Requests the current user's UUID (see BIOS_USER). |
| Peripherals | BIOS_COM_LIST |
Requests a list of connected peripherals. |
| Peripherals | BIOS_COM_SEND |
Sends a command to a peripheral. |
| Category | Command | Description |
|---|---|---|
| Disk | BIOS_DISK_RSP_CREATE_DIR |
Response to BIOS_DISK_CREATE_DIR. |
| Disk | BIOS_DISK_RSP_CREATE_FILE |
Response to BIOS_DISK_CREATE_FILE and BIOS_DISK_CREATE_STUB. |
| Disk | BIOS_DISK_RSP_DELETE_DIR |
Response to BIOS_DISK_DELETE_DIR. |
| Disk | BIOS_DISK_RSP_DELETE_FILE |
Response to BIOS_DISK_DELETE_FILE. |
| Disk | BIOS_DISK_RSP_FORMAT |
Response to BIOS_DISK_FORMAT. |
| Disk | BIOS_DISK_RSP_INFO |
Response to BIOS_DISK_INFO. |
| Disk | BIOS_DISK_RSP_LABEL |
Response to BIOS_DISK_LABEL. |
| Disk | BIOS_DISK_RSP_MOVE_DIR |
Response to BIOS_DISK_MOVE_DIR. |
| Disk | BIOS_DISK_RSP_MOVE_FILE |
Response to BIOS_DISK_MOVE_FILE. |
| Disk | BIOS_DISK_RSP_READ_DIR |
Response to BIOS_DISK_READ_DIR. |
| Disk | BIOS_DISK_RSP_READ_FILE |
Response to BIOS_DISK_READ_FILE. |
| Disk | BIOS_DISK_RSP_RENAME_DIR |
Response to BIOS_DISK_RENAME_DIR. |
| Disk | BIOS_DISK_RSP_RENAME_FILE |
Response to BIOS_DISK_RENAME_FILE. |
| Disk | BIOS_DISK_RSP_RUN_FILE |
Response to BIOS_DISK_RUN_FILE. |
| Display | BIOS_DISP_INFO_SEND |
Information about the display (mono/color, cols/rows; see BIOS_DISP_INFO_REQ). |
| General | BIOS_PERM |
Triggers user permissions request. |
| General | BIOS_POWER |
Describes the system's power state. |
| General | BIOS_USER |
The current user's UUID (see BIOS_GETUSER). |
| Input | BIOS_CONTROL_INPUT |
An incoming control key state change. |
| Input | BIOS_KEY_INPUT |
An incoming keystroke (see also BIOS_CONTROL_INPUT). |
| Peripherals | BIOS_COM_DEVICELIST |
A list of connected peripherals. |
| Peripherals | BIOS_COM_DISKLIST |
A list of mounted disks. |
| Peripherals | BIOS_COM_MONITOR |
The monitor UUID. |
| Peripherals | BIOS_COM_RECEIVE |
An incoming command from a peripheral. |
| Peripherals | BIOS_COM_REFRESH |
A request for disk drives to resend their active disk UUIDs. |