Configuration of the Master Series

Configuration guidelines for the Master Series
This section is taken from Support Group Application Note No. 203, Issue 1 dated 27th February 1992

After the Master series have had either their batteries or EEPROM replaced it will normally be necessary to perform some sort of re-configuration. This document describes all the configuration options available and what the default settings are when the computer is supplied by Acorn.

This only applies to the BBC Master 128, 512, ET and Compact models.


On the master series, the configuration is managed with the *CONFIGURE command. This takes one or two parameters, the setting to set and an optional value for that setting.

Like other commands it can be shortened as *CONF.
Note the . at the end is required when using the shortened version.

General Information

The *CONFIGURE commands must always be followed by a CTRL BREAK to initialise the settings in the machine.

It is possible to use Edit supplied with the BBC Master to created a standard file which contains all the *CONFIGURE options which could be used to re configure the machine in one go by using the *EXEC command.

The Master Compact EEPROM has a limited life of 10,000 write operations. The chip is easily replaced when this limit is reached.

If ROMs appear in the ROM table as being unplugged it is possible to re - insert then using the command *INSERT followed by the ROM Socket number eg. *INSERT 13

Default configuration

Configuration Default value Description
BOOT/NOBOOTNOBOOTDo not boot on power up
DIR/NODIRNODIRDo not initialise directory
FDRIVE06ms, ADFS precompensation enabled
HARD/FLOPPYFLOPPYDefault to floppy disk
IGNORE0No ignore character
INTUBE/EXTUBEINTUBEInternal Tube Interface
MODE7Teletext Mode 7

ANFS specific options

*CONFIGURE options that are available if ANFS is installed

View specific options

*CONFIGURE options that are available if System ROM 3.50 is installed

*CONFIGURE Baud <0-8>

Sets the speed of the RS232 serial interface

*CONFIGURE Boot / NoBoot

Sets the Boot action when the machine is switched on

*CONFIGURE Caps / NoCaps

Sets the keyboard caps lock

*CONFIGURE Data <0-7>

Specifies the data format used by the RS232 interface

*CONFIGURE Delay <0-255>

Sets the keyboard auto-repeat delay


ADFS: initialise with directory

*CONFIGURE FDrive <0-7>

Defines the step time or the use of precompensation in ADFS

*CONFIGURE File <0-15>

Defines the default file system by its ROM socket

*CONFIGURE Hard / Floppy

Sets if a hard disk or floppy disk is selected

*CONFIGURE Ignore <0-255>

Sets the printer ignore character

*CONFIGURE Lang <0-15>

Defines the default language by its ROM socket


Sets the default screen mode

*CONFIGURE Print <0-4>

Defines the printer port

*CONFIGURE Quiet / Loud

Sets the Bell (CTRL G) Volume

*CONFIGURE Repeat <0-255>

Sets the keyboard repeat rate in 1/100 second

*CONFIGURE Scroll / NoScroll

Sets the Scroll protect option


Enables the Tube co-processor

*CONFIGURE TV <0-255>,<0-1>

Configure the TV output

Last modified May 27, 2022: Fix section ordering (8d3ef4f)