acorn.co.uk/ftp/documents/acornusr/1994/mar94

Disabling Relocatable Modules
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In some situations, such as in a classroom, it may be considered desirable to 
disable some of the applications and relocatable modules which are an integral 
part of RISC OS.

Modules which are temporarily disabled will remain so until the machine is 
switched off. Modules which are "permanently" disabled (by *unplug) will 
remain so until the machine is reset via a Delete-Power On.

The routines for disabling relocatable modules may be inserted at the start of 
the !Boot or !ArmBoot file which is to be run when the machine is switched on 
or reset.

!Configure can be temporarily disabled using:

*RMKill !Configure

and can be unplugged using:

RMReinit !Configure | Put the module back if it is already unplugged
Unplug !Configure   | Now take it out.

 With Ethernet based networks, it is recommended that the Broadcast Loader is 
disabled. This may be achieved using: 

SetEval BLoader$Module 1
RMEnsure BroadcastLoader 0 SetEval BLoader$Module 0
If BLoader$Module Then RMEnsure EconetA 0 SetEval BLoader$Module +1 
If BLoader$Module=2 Then Unplug BroadcastLoader
Unset BLoader$Module

The script works by setting a flag, BLoader$Module, which is then altered 
according to a series of tests.

Taking this sequence a line at a time:

SetEval BLoader$Module 1           
| Set the flag to 1

RMEnsure BroadcastLoader 0 SetEval BLoader$Module 0 
| Check if the Module is there. If it is NOT then  
| set the flag to 0

If BLoader$Module Then RMEnsure EconetA 0 SetEval BLoader$Module +1
|If the module is there, check if Econet is there too. If it is, increment the 
|flag.

This gives us the situation that, if the Broadcast Loader is already disabled, 
the flag is set to 0. If the Loader is enabled and the Econet module is 
enabled, the flag is set to 1. If the Loader is enabled and Econet is software 
unplugged, the flag is set to 2.

If BLoader$Module=2 Then Unplug BroadcastLoader
|If the flag is set to 2, disable the Broadcast Loader

Unset BLoader$Module 
| Remove the system variable used for the flag from memory


A5000 External Floppy Drives and RISC OS 3.1
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
It has been found that some 5.25" floppy drives connected to A5000s have 
stopped working when the machines are upgraded to RISC OS 3.1.

The solution to the problem is to move link 21 on the main PCB from position 
1-2 to 2-3.

An Application Note, which can be obtained from Acorn Approved Dealers and 
Education Centres, has been written to detail further configuration procedures 
for installing external floppy drives.

New Products and Upgrades
~~~~~~~~~~~~~~~~~~~~~~~~~
!Printers version 1.22 

!PhotoView, Acorn's PhotoCD Support System incorporating CDFS 2.21: £34.99 ex 
VAT

These are available from Acorn Approved Dealers and Education Centres.

Level 4 Release 3, including Acorn Application Accelerator:  £99 ex VAT, incl. 
p&p

This is available from:

Vector Services
13 Dennington Road
Wellingborough
Northamptonshire NN8 2RL

Cheques to be made payable to "Acorn Direct."