From: K3H (ALBERT SCHOFIELD)
Subject: TAPE TO DISC ON THE BBC B
BUGEYES II is a particularly
difficult game to transfer to disc as
the last part has changing filenames
and is also locked in a special way so
that if it is unlocked and then
relocked it will not work. Also it
needs to be downloaded to &900.
BUGEYES II is in five parts:-
STARMAN, BUG1, SCREEN, BUG2 and
changing filenames.
The first part, STARMAN, is a basic
program and has hidden lines. Load
this in from tape and delete all lines
from 41 upwards using DELETE41,1040.
This will also delete the hidden
lines. Add the following lines:-
50 *KEY0 *RUN BUG1|M*RUN BUGEYES|M
60 *FX138,0,128
70 END
Save this to disc as STARMAN.
The next two parts, BUG1 and SCREEN
can be transferred to disc unaltered.
The fourth part, BUG2, needs to have
it's execution address altered so load
it in using *LOAD""1900. Save it to
disc using *SAVE BUG2 1900+356 709 400
To load in the last part an unlocking
utility will have to be used. Also use
*OPT2,0 to force the changing
filenames to load. Load it in at
&1900. Ignore the File? messages.
Save it to disc using:-
*SAVE BUGEYES 1900+4F00 1E0A 900
This file will have to be downloaded
to &900 using the method of your
choice. If you have the WATFORD DFS do
not use *MRUN as this clears the
screen. Switch the computer off then
on again. Chaining STARMAN will now
load and run the game. The top of the
screen will be corrupted by the
downloading but this does not
interfere with the playing of the
game.
If you have sideways ram and you wish
to have a perfect load then the last
part BUGEYES, instead of adding a
downloader, can be put into two rom
images. It is too long to go into one.
Save the rom images as BUG1R and
BUG2R. Add the following lines to the
first part, STARMAN, instead of as
shown earlier:-
50 *KEY10 CLS|M*RUN BUG1|M *ROM|M
*OPT1,2|M*RUN BUGEYES|M
60 ?&FF30=0:*LOAD BUG1R 8000
70 ?&FF31=0:*LOAD BUG2R 8000
80 CALL!-4
Chaining STARMAN will now load the
rom images and run the game for a
perfect load.
To: 999 (all members)
ReplyTo: D5B (Jon Ripley)
From: K8G (Jonathan Harston)
Subject: Reading DOS disks
There are a variety of methods for
getting BBC data into a PC. As well
as BBC disk readers for the PC as Jon
mentioned last month, there are
various DOS disk readers for the BBC.
Of these, I know about:
Petrov DOS FS:
A DOS filing system for Master or B+.
Allows full filing-system access to
DOS disks. There are some
unimplemented features, notably there
is no *RENAME command, but it is fully
usable. It has to run in sideways ram.
DOSUtils, DOSCopy, DOS-BBC
Programs that allow you to transfer
files between types of disks.
To access any DOS disks you need the
1770 controller as the 8271 in the BBC
B can only do single density. You can
access disks up to 720k in size. The
1770 cannot access 1.2M or 1.44M disks
(the ones with two holes in them)
The programs are useful for
transferring between disks. If DOS-FS
was more fully implemented it would be
the better method. At some point I
intend to implement DOS FS as part of
HADFS, but things seem to be plodding
a bit just now.
All the above programs are available
from JGH PD on disk ??. Petrov DOS-FS
was on 8-Bit issue disk 51.
To: 999 (all members)
ReplyTo: D6E (Richard Harker)
From: K8G (Jonathan Harston)
Subject: Keyboard DIP switches
The bank of eight DIP switches at the
bottom of the keyboard define various
start-up options. Numbering from left
to right, they are:
1: DNFS filing system priority, DISK
or NET takes precedence.
2: The only thing I know that uses
this bit is HADFS. It sets whether
to use floppy driver or external
driver for drive 1.
3:
4: Disk speed, similar to FDRIVE
configuration setting on Masters:
sw3 sw4 step settle load
1 1 4ms 16ms 0ms
1 0 6ms 16ms 0ms
0 1 6ms 50ms 32ms
0 0 24ms 20ms 64ms
You can try selecting the fastest
speed your drives will operate at to
speed up disk access. Most modern
drives will happily go at setting 3.
5: Reverses action of Shift-Break and
Break.
6:
7:
8: Startup mode.
The link setting are copied to Osbyte
255 on Ctrl-Break, so to see what the
effects would be without setting the
switches, use *FX255,newvalue where
newvalue is made up from the bits
listed above, in the reverse order, ie
switch 1 -> bit 7; switch 8 -> bit 0.
To: 999 (all members)
ReplyTo: D6E (Richard Harker)
From: K8G (Jonathan Harston)
Subject: Socket on keyboard
The socket to the left of the keyboard
is for inserting serial PHrase ROMs,
or PHROMs for use with the speech
system. Most people who do use the
'ashtray' as the hole was known
usually put an external sideways Rom
socket there instead.
To: 999 (all members)
ReplyTo: D6E (Richard Harker)
From: K8G (Jonathan Harston)
Subject: ULA Heat Sink
Why is the heat sink there? ... To
get rid of the heat of course. This
question makes no sense.
To: 999 (all members)
ReplyTo: 0E7 (F.W.Nevin)
From: K8G (Jonathan Harston)
Subject: Fate of 3.5" disks
How can CD-Roms replace 3.5" floppies?
CD-ROMs are a read-only media. There
will always be a need for a writable
storage medium on which you can carry
information from one machine to
another.
What do you mean by a 3.5" DD PSU? Do
you mean a disk drive PSU... in which
case most electroncs dealers will be
able to comply. Or do you mean a 3.5"
DD disk drive. In which case, again,
most electroncs dealers will be able
to comply.
Internal (ie powered by the computer)
3.5" disk drives currently cost around
£30. (<- look! a pound sign!)
To: 999 (all members)
ReplyTo: D9F (Gary Scott)
From: K8G (Jonathan Harston)
Subject: 3.5" disk drive
A switchable 3.5" disk drive? Why?
All 3.5" disks are 80-track, so what
point would there be in switching the
drive to 40 track?
Do you need anything other than the
disk drive and ADFS to use it? Well,
you need the 1770 controller inside
your machine. ADFS will not access
floppies without that, but I seem to
remember from earlier messages that
you do have the 1770. Hmm... a
connecting lead... A spare power
socket... About sixty square inches of
space on the desk at the side of the
computer...
To: 999 (all members)
ReplyTo: D6K (Mike Mallett)
From: K8G (Jonathan Harston)
Subject: CP/M and hard drives
Back in issue 51 you had a message
asking how to use a hard drive with
CP/M. I wrote a reply, but it seems
to have got lost. Anyway...
The BIOS (Basic Input/Output System)
supplied with the Acorn Z80 only
provides access to two drives, floppy
0 and 1. The simplest way to provide
dard disk support is to patch the BIOS
to make it access a file on the hard
drive whenever drive, eg C: was
accessed. I'm working on this just
now, and I'll send you a copy as soon
as it's ready. A better method would
be to allow full access to the BBS
file structure from CP/M. This is a
bigger job, as it requires rewriting
the BDOS, not just patching the BIOS.
I've been planning to get around to
doing this for some time.
To: 999 (all members)
From: D6G (SPROW)
Subject: Inside out
Last month Richard Harker was puzzled
about the machine he has:
1)SWITCHES ON THE BOTTOM OF THE
KEYBOARD PCB
These are option links (replaced on
the Master by the *config. options
stored in battery backed RAM) that
allow configuration of the machine on
power up.They are not normally fitted
to the PCB,to save money,but may be
fitted (Maplin order code XX27E) very
easily.You just happen to have a board
that has them already added.
2)THE ASHTRAY
On a BBC B the brown keyboard overlay
has a punch out hole on the LHS,this
was intended to be removed when the
speech system was added.Unfortunately
Acorn were a bit late in releasing
this and not many people bought it
when they did - you have a machine
which has had it fitted at one ppint.
The 20 way edge connector was for
games cartridges which were considered
as additional PHROMs to the speech
system.They would load as fast as
disks,but I've never come accross any
to try.
3)IC 61-68
Using the BBCISS7 program from my
homepage,this reveals that they are
indeed RAM,perhaps yours was a model
A in a previous life.I'd not recommend
unplugging them.
4)THE HEATSINK
On the right inside is on the Ferranti
ULA (used as part of the video system)
which was rather poorly designed and
overheated.Acorn redesigned it later
and you don't need a heatsink on
those.
5)AB ELECTRONICS
They built the BBC in Wales.
So there we go.
To: 999 (all members)
From: D6G (SPROW)
Subject: Composite video
Last issue,I was asked how to make the
colour modifications to BBC's for the
composite video.
I explained that Acorn left it B&W as
they expected the RGB system to be
used more,and that having colour
composite video does in fact degrade
the quality of the RGB side.
I have now found,after much trawling
the details of how to modify ALL board
issues:
On Issue 1 ,2 & 3 board a 470
picaFarad capacitor should be fitted
between the emitter of Q9 (identified
by an "e" next to one leg) and the
base of Q7 (the central Leg).
On Issue 4 and later, the capacitor is
on-board and can be connected simply
by fitting link 39 which may be found
next to the modulator in the far right
hand corner of the PCB.
On the BBC Model B+ link S26 should be
made.
On Master 128 issue 1 boards a 470
PicaFarad capacitor should be
connected between the East Leg of R137
and the East Leg of R153 which are
located directly to the East of the
modulator.
Connections should be made on the
component side of the PCB with the
leads of the 470 PicaFarad capacitor
being soldered directly to the leads
of the two resistors.
On Master 128 issue 2 boards link LK11
should be made.
There,I think that covers just about
every machine type!
Best of luck,
Robert Sprowson.
To: 999 (all members)
From: D6G (SPROW)
Subject: Doomsday
The number of people fretting about
the year 2000 causing problems with
the Master 128 has been increasing.
All of the disk user groups,such as
EUG and 8BS have had articles,but I
can assure you not to worry.
I have produced a ROM that will
correct the problem & also extend the
century range available to Jan 1st
year 1800 until Dec 31st 2199.
These can now be ordered for my usual
ROM prices,`4,including instructions.
The program comes on an 8k ROM,and
uses Acorn calls only.If you're not
using a Master,but do have a real time
clock,check in your manual before
ordering that it supports OSword 14
and 15 and OSbytes 161 and 162.There
is also a program on this disk to
detect whether these calls are
supported which you should try before
ordering.
Not only does it include the date
fixer but also a *DRIVE to *DIR:
converter to help ADFS run programs
written with DFS in mind (this patch
is also available from my web page).
As a bonus there's a current working
directory command,which shows the CWD
if you use *DIR with the drive
parameter missing.This is also on my
web page,along with many other titles.
If you're not using a Master,you'll
find the built in *ROMS command and
*SHOW command very handy.
To improve reverse compatability from
Master to BBC the *CLOSE command has
also been included.
An additional *CONFIGURE command sets
the current timezone,which can be
used to toggle between BST and GMT.
Please note that this should NOT be
run from sideways RAM.
Please state when ordering:
1)Your name
2)The return address
3)Whether you are using a Master/other
All in all this looks to be a very
handy ROM - after all time is
literally ticking away...
Web page:
www.york.ac.uk/÷rps102/bbc/bbc.htm
Write to R.P.Sprowson
6 Bollinbrook road,
MACCLESFIELD,
Cheshire.
SK10 3DJ.
Fax (01625) 431067
Email rps102@york.ac.uk
8BSmail D6G
To: 999 and D6B (Richard Harker)
From: D5B (Jon Ripley)
Subject: Help Offered For Issue 4 BBCs
For ease of answering I have
reproduced Richard's questions here...
1) On the keyboard, in the bottom
right corner a bank of 8 dip switches
has been added. What are they for?
These DIP switch settings reflect the
default setting of start up options as
set by OSBYTE 255. (*FX 255)
There is a space on the bottom right
of most BBC keyboards where a bank of
switches can be added if not already
present.
These switches allow a small degree of
system configuration.
Each of the eight switches corresponds
to a bit of the data. Bit 7 on the
leftmost switch to bit 0 on the right.
Switch on for 1 or off for 0.
The format is as follows...
Bits 0-2 Screen mode (000=0 to 111=7)
3 = 0 to !Boot on Shift-Break
= 1 to !Boot on Break
4-5 Set disc speed
= 00 for fastest through to
11 for slowest
6 Reserved
7 = 0 DNFS starts in DFS
= 1 DNFS starts in DFS
Where the switches are not present
they are read as being switched off.
On the Master and Compact, only bit 3
has any effect, the others being
ignored. There are no equivalent switch
settings on the Electron.
2) On the keyboard, in the middle
left, a blue socket has been added. It
is hard to describe. It has 2 rows of
10 pins, and then further, on the same
piece of plastic, 2 rows of 2 pins.
What are these for?
I am not sure what these switches are
for but I remember something about a
bank of 8 switches (or links) which
set the ECONET station number of the
machine (also appears at &FE18 in the
memory map).
3) On the keyboard, at the top left,
about 4cm from the connector to the
main computer, there is a row of of 10
pins. These are connected to the
socket as described above. Does this
connect to PL14 on the mother board.
What does it do.
This applies only to the BBC B and B+.
Where no pins are present it is
possible to solder a row of pins to
the keyboard. It connects to the row
of pins directly beneath it.
This connection is used when a speech
upgrade is fitted to the BBC to relay
infomation.
4) ICs 61-68 on the motherboard are
socketed. If I am right in thinking
that these are memory chips, would
removing them make my computer 16k?
Not having a BBC to hand I can't help
with this one at the moment.
5) A number of other chips on the
board are socketed (eg the SA5050) was
this common practice on the earlier
issues BBCs.
I am not entirely sure of the
reasoning behind socketing some of the
roms on some motherboards whilst
soldering on others but generally
there is more of it on earlier BBCs.
To: 999 (all members)
From: D5B (Jon Ripley)
Subject: Tape to disc on the BBC B
Many thanks to Albert Schofield for
his series on transferring tape games
to disc.
Transferring old BBC tapes games to
disc can be quite a daunting task for
many users even with games that have
no protection at all.
Duplicating taped games nowadays is
quite a simple task, all that is
required is a simple hi-fi system.
Games producers began to use quite
sophisticated protection techniques to
stop hackers examining the inner
workings of their games.
The operating system allows tape files
to be locked and provides a method
that most modest users will be unable
to bypass.
Efforts to deter the more sophisticated
hackers included using a different way
of saving the files to tape so only
their own tape loaders would work. A
good example of this is the Psycastria
game, listening to your tape of this
game you will notice it sounds totally
different to the average tape game.
But back to discs...
More next time!