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THE JOURNAL
OF THE
BRITISH APPLE
STSTEMS
USER GROUP
October 1983 ai VOLUME 3 No. 5
Page 2
HARDCORE - The Journal of the British Apple Systems User Group
1983
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October 1983 HARDCORE - The Journal of the British Apple Systems User Group Page 3
3g
hardcore CONTENTS
THE JOURNAL OF
THE BRITISH APPLE SYSTEMS USER GROUP
4 The Apple speaks to the BBC
P.0.80X 174 WATFORD Wo2 6NF Nik Kelly
9 Apple Magazines Keith Chamberlain
BASUG Ltd. is @ non-profit-making Basug Telephone
Company limited by guarantee. LL Mainframe Interview
13 More on the 737 Margaret Wood
‘ 15 Education Norah Arnold
Basug Committee Exec Tip Martin Rogers
18 Book Review Jim Panks
19 Fast Circles Ray Harris
Bob Raikes Chairman poets Series
22 Permanent & Temporary Strings
Norah Arnold Secretary ;
: Richard Teed
Tony Williams Tressiter a5 Sap iwacs Lb EERy
Legg Administrator 9 Communications Update
Jim Panks Software Library : Puantla Reterord
John Rogers Meetings 51 Ceemac
John Weilsman Membership John Molloy & Colin Holgate
Quentin Reidford Communications HA eee eae y Richard ‘Teed
Keith Chamberlain Lit. Library 9g Diary
Yvette Raikes Hardcore Editor
Peter Blair,
John Rodger &
Mike Siggins Assistants
seve eeeeseeeessesesseessessessessesssesses
Many regular features such as the editorial,
chairman's corner, etc. are missing from
this issue due to lack of space.
BANKERS INTERNATIONAL
APPLE CORE
National Westminster Bank PLC,
Brompton Square, London SW3 IHH. ™
— MEMBER OF THE
INTERNATIONAL APPLE CORE
COPYRIGHT (C) - The contents of this journal
are copyright of the British Apple Systems
User Group and /or the respective authors.
However permission will normally be granted
for non-commercial reproduction by user
Rroups affiliated to the International Apple
Core, provided the author and source are
properly credited.
HARDCORE is produced using Applewriter
I, and printed on an APTEC Flowriter with
a Madeleine Daisy-wheel
Front Cover: Design by Ray Harris. See
artic \s i Ye
The opinions and views expressed are those ion Rest Circles: in this: Lasie
lof «the various contributors, and are not
Necessarily supported by the British Apple
Systems User Group.
Page 4
HARDCORE - The Journal of the British Apple Systems User Group
October 1993
The Apple Speaks To The BBC
By Nik KELLY 8 August 1983
Introduction.
This article describes the programs I have
developed to link an Apple with a BBC'R via
4800 Baud RS232. The BASIC is simplified by
three short machine-code programs, a Call
-APPLE ‘line input' for reading disk files
and my serial ‘Inline and ‘Outline’
routines.
Request To Send?
The two obstacles to interfacing an Apple
are the Disk Operating System ( DOS ) and
the lack of a ‘line input’ in Applesott. Apple
DOS is involved in every I/O task. All
conventional text transfers must pass
through its input and output vectors but,
sadly, DOS cannot keep separate input and
output streams.
If I want to print a text file from the
disk, Imust use a program like
'N - 0: REPEAT : (d)OPEN : (4)POSITION, RN
: INPUT LINE AS : (d)CLOSE : N = Nel =
(@)PR# printer : PRINT AS: (d)PR#O : UNTIL
end of data’
The reverse trip is little better,
AOPEN FS : (A)CLOSE F5: REPEAT Ad)INA2 =
INPUT LINE AS : (d)IN#O : (J)APPEND F$ :
PRINT AS: (d)CLOSE F$ : UNTIL end of data’
The REPEAT UNTIL is usually implemented with
'ON ERR GOTO'. INPUT LINE must use GET,
looped until the end of the line, to allow
commas, quotes and colons to be transferred:
One alternative to the resulting ‘whirr then
wait' is to put the strings into an array,
then APPEND or PRINT it all at once. It
takes a lot of RAM, though. A de-tokenised
program can expand by a factor of five!
These programs bypass both of those
problems. The serial input and output do not
pass through DOS, so the IN// and PR# are not
needed, and the 'Line Input’ is pertormed by
an ampersand utility.
The Hardware.
1) The BBC Micro.
The 'B' has an RS 423 interface with Baud
rate and bit pattern selected by software. The
5-pin DOMINO socket carries RS 232
compatible CTS/RTS, Din/Dout and Ground
signals, as shown in the BBC Guide. The
plugs are reversible, so PLEASE mark the top
clearly!
The BBC is a strange machine for an Apple
owner. There's a 6502 CPU, ROMs at the top
of RAM, memory-mapped I/O and ROM-paging,
but the organisation seems weird. It isn't. The
simplest way to look at it is to imagine
that I've used one of those expensive
utilities that relocates DOS onto a second
RAM card. Now, I'd have FP, INT and DOS on
different 16 K pages, to match my BBC's
BASIC, WORDWISE, Forth and DFS 16K chips.
The big difference is that the 4K Apple
Monitor gets over-layed, while the 12 K BBC
equivalent, the OS, is common to all. Other
than that, the similarities are remarkable. The
Monitor contains the slot and cassette 1/O
routines, the screen editing, graphics
(Lo-res), even sound: the Beep! for ctrl-G. The
BBC OS has those, with suitable extensions
for the extra hardware, but it also has a
Command Line Interpreter to ease the access:
DOS grabs every printed line beginning with
ctrl-D, while the BBC OS intercepts commands
marked by an asterisk.
The serial ‘effects’ commands are;
"FX 2,1 ( Take input from serial,
locks out kbd
) (Restores default
* FX 5,2 (Printer is serial
1 ( detault Centronics
“FX 6,0 (Allow 'line-feeds'
10 ( default, blocks Ifs
*FX7,6 (talkat 1150 3 600
5 2400 Baud
8,6 (hear at 2 300 4 1200
6 4800
* FX 156,20,227 (8 data, noPar, 16 = |,
20 = 2 stop bits
Low FX calls are quoted from the BBC Guide.
FX 156 is from Acorn leaflet BROO1-6/83.
2) The Apple.
The Apple has a disk controller in slot 6
and a serial card in slot 2, The software in
this card's PROMs is not needed, as the
programs go directly to the 6850 ACIA. This
uses two locations, CONTROL at $COA4 *
49316, and DATA at SCOAS = 49317. Baud rates
between 150 and 4800 are selected by *
October 1983
HARDCORE - The Journal of the British Apple Systems User Group
Page 5
rotary switch. These addresses are different
for other slots and cards, but the programs
are easily changed. Modifications for other
ACIA chips are welcomed.
3) Cables.
My serial card has a 12 inch ribbon with
header-plug and D-25 socket. 1 made a
‘null-modem' adaptor for the BBC, wired CTS
to RTS, Din to Dout and vice-versa, with
common Signal Ground. If my cabling was
based on D-25, I would have used a D-25
null-modem and an in-line adaptor, CTS to
CTS, Din to Din etc.
For short distances, the cable can be a
piece of 5-way ribbon, but for lengths over
a metre please use quad screened core, or
similar. As with any signal carrier such as
printer or joy-stick cables, route the
serial link away from sources of
interference.
The ACIA butter chips protect against open
and short-circuits on the RS 232 lines, and
are not vulnerable to moderate levels of
static. They will NOT survive telephone,
current -loop / Teletype or 'mains' voltages
= nor will the computers!
The Software.
The software deals with strings. For speed,
my serial 1/0 requires the first variable to
be the send/receive string, so
10 A$ = ™ REM I/O VAR.
The & Utility is not limited in this way.
The machine -code occupies approx 160 bytes
of the Apple's page $300, with the Line
Input utility for disk files, and the serial
OUTLINE and INLINE programs. I've kept them
Separate as you may not need all of them.
First, at $300 for a CALL 768 or BRUN, is
the jump to SETUP which sets the serial
parameters and establishes the $3F5 jump for
the ampersand, This is followed by jumps at
771 and 774 to OUTLINE and INLINE
respectively. I didn't like using so many
jumps but there is no significant delay and
the CALLs are easy to remember.
After SETUP comes D. A. Lingwood's
SINPUTLINE utility, from ‘Call Apple in
depth #1 1981", When 1 discovered it
recently, I realised that it was too neat to
beat. It reads upper and — lower-case,
punctuation and quotes into the keyboard
buffer through the current DOS vectors. When
it reaches RETURN or CHRS(13), it points the
named string to the data, If you need to
save the string, you must use a line such as
"AS = ™ + AS ' before the buffer is
re-used.
Next is OUTLINE. This sends the contents of
the I/O string to the serial port. The
format is ' A$ = "MESSAGE" : CALL 771 '
Using the ampersand, '40A$='™ 50& A$
60 CALL 771 :GOTO 50 ' can READ a text file
fast enough to keep my disk spinning.
Applesoft stores its strings in two parts:
VARSP @ $69,6A points to the start of the
variables, Strings have two bytes for the
name, then a byte for the length, then the
address of the text in lo,hi format, which
may be anywhere in memory. My program copies
the length and lo,hi bytes into page-zero,
checks for a null string, then initialises
the Y register as the position counter.
For cach character, the program calls the
READY subroutine. This loops until ‘bit 1'
of the ACIA CONTROL register goes to 1,
showing that the line is free for use. The
first character is then copied from the
string and put into the DATA register,
automatically setting CONTROL ‘bit I' to
zero. OUTLINE then loops back until the
entire string has gone. Finally, a CHRS(13)
RETURN is sent to complete the line.
INLINE is very similar, but the I/O string
should be filled with spaces before use to
reserve space for the incoming message. Again,
it copies the string's lo,hi address into
page zero. The Y register is used as the
length counter, while the X holds the
bit-pattern that will set the ACIA to show
BUSY and prevent an over-run. The BUSY is
turned off, and a rapid loop checks for a
received character. A 1 in ‘bit 0' shows
there's a catch, when the gate is promptly
set to BUSY. The DATA is read, and if it
isn't a CHRS(13), it is added to the string
text. When the end-line arrives, or the
length counter fails-safe at 256, the length
is reduced by onc and this result is put
into the string header.
The Uses.
I hoped the link would save the cost of a
disk for the BBC and allow me to treat the
BBC as an intelligent graphics display. The
serial software took too long to develop. Both
hines now have disks and the graphics are
* to program on the BBC, but the link
Page 6
HARDCORE - The Journal of the British Apple Systems User Group
October 1983
has proved useful. My current word-processor
is Wordwise, in the BBC, so that machine has
the ‘parallel’ Epson. The Apple uses a old
40 column Silentype for ‘quickie’ listings,
but anything else goes via the BBC. The
BBC's built-in symbolic assembler, though
fine for little programs, is no match for
LISA on the Apple. The assembly listing in
this article was put on disk by LISA 2.2,
then sent through the link to Wordwise. I
just had to remember that after 1 typed '*FX
2,1" at the BBC, the Apple needed to send a
‘Return’ and an ‘Escape’ to put Wordwise in
Insert-mode, then finish with an ‘Escape!
and '*FX2! to set it free!
The Tale
At the start, using the serial card's
software and a ‘receive’ patch for the BBC's
0.1 OS, the link ran at 300 Baud. The
Apple's looped GET statements effectively
halved that, which meant that transfers
averaged five minutes.
While I waited for the BBC's promised 1.0 OS
ROM, | used its 1200 Baud tape socket and
tried to improve the 'receive' patch. Both
machines had 6850 ACIA chips in their
interfaces, but while the Apple's was well
behaved, the BBC's would not follow the data
sheet. I knew that a ULA chip intercepted
some of the CONTRO! bits, but I couldn't get
any information for several months.
The BBC's ‘receive! was stalled, so I turned
to the ‘send’, The higher Baud rates
promptly over-ran the Apple. I checked for a
disconnected hand-shake line, discovered
that the serial card wasn't providing the
signal! 1 couldn't believe it. I'd paid
extra for a versatile serial card, so surely
that signal was in its list of options? Yes
and no. The hardware was there, but fitting
all the clever printer routines into the
card's PROMs had squeezed out the dozen
bytes needed for a hand-shake loop.
1 abandoned IN#2, wrote a mini-assembler
program to provide hand-shake and store the
received character at the end of the
program. TheBASICGET then became 'CALL 768
: AS = CHRS( PEEK( 790 ))'. The BASIC ran
much quicker without those DOS commands!
After losing another struggle with the BBC
patch, I wrote a prototype INLINE. To my
surprise, I had some trouble with handshake
above 600 Baud. Several ot the standard
loops just couldn't keep up, and 1 spent
weeks trying different’ ways’ to stop the
machine-code doubling or dropping initial
characters.
At that stage, I got some information on the
BBC chips, and saw how to turn the BUSY on
and off quickly. Fitting that to the
scarcely documented BBC I/O vectors took
some weeks, but I finally sent a large file
to and fro at 4800 Baud. That was a Saturday
night. On the Tuesday, a packet arrived with
Wordwise and a OS 1.2 chip ss.
The BBC machine had one final trick to play:
The OS 1.2 used different default parameters
for the serial. Until 1 could check the
chips, I thought I'd blown a buffer. Even
then, | had to wait for Acorn to send the
*FX 156 data.
The next step.
The programs can be improved. Using named
strings through-out, monitoring several
ACIAs and linking three or more machines in
a loop come to mind, If the Out of one is
connected to the In of the next, and every
message is preceded by two bytes of address,
then you could specify one, many or all of
16 machines without complex addressing. Just
AND the address with your own, which has a
single bit set. If not yours, then send the
message on. If yours, then clear that bit
and send the message on, If both bytes of
address come in as zero, then it has been
all the way around and you can dump it. To
do it properly, of course, the I/O would
need interrupt programming.
Recently, 1 became interested in linking
several machines after watching my young
cousins playing (?) D&D on a map-board. I've
seen many computerised Adventure games, from
Cavern to Zork, The Valley to Wizardry and,
real-time, Aphsai to Hellfire, but everyone
is really a solitaire. When you're knee-deep
in zapped whatsits and they're still coming,
a map can be a very lonely place. Also,
those puzzles = and-—shazards —are
algorithm-bound, There are few opponents or
partners better than the live variety and,
provided the game is real-time, the
programming could be — simplified. For
instance, the BASIC ROMs can serve as the
map! .. Any ideas?
The programs should soon be available from
the software library,
October 1983 HARDCORE - The Journal of the British Apple Systems User Group Page 7
0 REM APPLE DISK TO WORDWISE O3F5 14% AMPERS EQU $03F5
1 A$ = "": REM I/O STRING COAS 15) ACIAC EQU SCOAG
10 CALL 768 COAS 16 ACIAD — EQU ACIAC+1
20 CALL 771 0003 17 RESET — EPZ $03
30 INPUT " FILE NAME ";FS$ 0015 18 SERON — EPZ $15
} 40 DS = CHRS (4) 0055 19 SEROFF EPZ $55
50 A$ = CHRS$ (27): CALL 771 0300 20 ; 8 DATA NOPAR | STOP
60 PRINT : PRINT DS"OPEN"FS 0069 21) VARSP EPZ $69
70 PRINT D$"READ"FS OOFA 22 ZP EPZ SFA
80 ONERR GOTO 120 0300 23; SFA - $FC USED
90 AS = "* 0002 24 MASK EPZ $02
100 & AS 000d 25° EOL EpZ $oD
110 CALL 771: GOTO 100 OOFD 26 2P2 EPZ
120 PRINT DS"CLOSE” 0300 27°; USES SFD - SFE
125 POKE 216,0 0300 28;
130 A CHRS$ (27): CALL 771 0300 29 5
140 *FX2": CALL 771 0300 30;
150 REM FROM *W. 0300 31 3** SETUP JUMPS **
160 REM *FX7,6 0300 32 5
170 REM *FX3,6 0300 4CO903 33 BRUN IMP SETUP
180 REM *FX156,16,227 0303 4C3D03 34 OUT IMP OUTLIN
} 190 REM *FX2,1 0306 4C6FO3 «35 IN IMP INLINE
200 REM THEN APPLE TAKES OVER 0309 36 3
0309 AI4C 37 SETUP LDA #$4C
0308 8DF503 38 STA AMPERS
0 REM BBC TO APPLE DISK 030E A923 39 LDA #ENTRY
1 AS = "": REM 1/O STRING 0310 8DF603 40 STA AMPERS+!
lo S$=" "; FOR.N = 1 TO Sit 0313 A903 41 LDA /ENTRY
AS = AS + S$: NEXT 0315 8DF703 42 STA AMPERS+2
20 INPUT " TO DISK FILE NAME ";F$ 0318 A903 43 LDA #RESET
30 DS = CHRS (4) 031A 8DA4CO 44 STA ACIAC
40 PRINT DS"OPEN"FS 031D A955 45 LDA #SEROFF
50 PRINT DS$"WRITE"FS O31F 8DANCO 46 STA ACIAC
60 CALL 774 0322 60 47 RTS
70 IF AS < > “ENDFILE" THEN PRINT 0323 48;
AS: GOTO 60 0323 49 3 END OF SETUP
80 PRINT DS"CLOSE"FS 0323 50;
90 PRINT "DONE |" 0323 Sl 5
100 REM TEST 0323 $2 3
0323 33;
0323 54 oye** & INPUT ###
The Assembly listing. 0323 5S 5
0323 36 3(C) DA _LINGWOOD
0323 57; CALL-APPLE 1981
0800 i 3 0323 58 ;IN DEPTH #1 P126
0800 24 0323 99° = INPUTLINE AS
0800 3 5*** LINE 1/0 ##* 0323 60 5
0800 a 3 0323 6l 3
0800 5 3 NIK KELLY 0323 20E3DF 62 ENTRY JSR $DFE3
0800 6 3 6 AUGUST '83 0326 A200 63 LDX #$00
0800 ts 0328 2075FD 64 ISR $FD75
0800 85 032B A000 65 LDY #$00
0800 9 3 032D 8A 66 TXA
0300 10 CALL768 ORG $0300 0326 9183 67 STA ($83),Y
0300 1 OBI $1000 0330 C8 68 INY
0300 12>; 0331 A900 69 LDA #$00
0300 13 ¥ 0333 9183 70 STA ($83),Y
Page 8
HARDCORE - The Journal of the British Apple Systems User Group
October 1983
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yee INPUTLINE ***
3 NIK KELLY
; 30 JULY 1983
3
;
1
AS _IS_IST VAR
BUT LEN() = 295
COPY A$ LO,HI
NLINE LDY #$03
LDA (VARSP) ,Y
STA ZP2
INY
LDA (VARSP),Y
STA ZP2+1
} SET FOR QUICK ON/OFF
Loy #$00
LDX #SEROFF
LOOPS LDA #SERON
STA ACIAC
3 CHECK FOR DATA
LDA #S01
LOOP 5 BIT ACIAC
BEQ Loop>
3 ADD IT TO STRING
STX ACIAC
LDA ACIAD
CMP #EOL
BEQ EXIT
STA (ZP2),Y
INY
BNE LOoP4
3 STORE NEW LENGTH
EXIT DEY
TYA
Loy #$02
STA (VARSP),Y
RTS
END OF INPUTLINE
poss Sse as
ND END
«**** END OF ASSEMBLY
October 1983
HARDCORE - The Journal of the British Apple Systems User Group
Page 9
Nik says he is prepared to tackle enquiries
concerning the article, but please enclose
an SAE of a sensible size. He is not
equipped to discuss Pascal, Z-80, 6809, etc.,
as he is a 6502-er until the 68000 add-on
for the BBC comes along.
Write to:
Nik Kelly B.Sc. AFBIS
ty, Gana vanes,
Hang,
ih etniti
Apple Magazines
by Keith Chamberlain
Several magazines on the market are
dedicated to the Apple the best of which is
NIBBLE, which is only available from the
States, Next comes CALL A.P.P.L.E. which has
been obtainable in the UK. and finally
WINDFALL.
Other magazines such as PRACTICAL
COMPUTING, PERSONAL COMPUTER WORLD,
QUESTIONS AND ANSWERS, COMPUTER AND
VIDEO GAMES and a host of others sometimes
carry interesting articles and programs for
the Apple, but should be viewed at your
local newsagents before purchase as they may
not be of much benefit at times.
At the top of my list is NIBBLE which has an
amazing number of articles, reviews and good
programs that actually work. The main
problem is getting your copy from the states
and the price. Also available are NIBOLE
EXPRESS Vols |, 2 and 3 which are splendid
value and contain selected articles from all
NIBBLES of 1980-81-82 which include all
kinds of programs including utilities and
games,
Next comes CALL A.P.P.L.E. the american
apple user groups magazine which contains
hints and tips, programs, reviews and for
A.P.P.L.E. members, special offers on
software and hardware, although not all of
these are available in the UK. CALL
A.P.P.L.E, can be received by subscription
direct by becoming a member. It has been
available in the UK but the company selling
it has just folded up so its future
availability is uncertain.
There are also special editions called Call
Apple in Depth, of which at the moment there
are three :-
1. All about Applesoft
2. All about Pascal
3. All about DOS
These are approximately E12 each and the
editions | have are 1 and 3, which I have
found to be extremely helpful especially
number | whose cost was covered by one
program alone.
Finally we have WINDFALL which, although it
is apple dedicated, has its ups and downs as
far as value is concerned, but this apart it
does have some quite good hardware and
software reviews, interesting articles and
the occasional piece of information that
makes its purchase worthwhile. This is
another magazine that has started to appear
in newsagents and may be worth thumbing
through before purchase.
A new quarterly magazine called ORCHARD
comes on the market in autumn which has
exclusive rights from Nibble to market their
editorial and software in the U.K. In other
words they will be printing Nibble articles
and programs. ORCHARD will be available from
newsagents,
Basug Telephone
Your BASUG telephone contact is Fran Teo and
you can phone her on weekdays and on weekday
evenings until 8 pam. on:
St. Albans (fli) att
Page 10 HARDCORE - The Journal of the British Apple Systems User Group October 1983
7] OUTSTANDING PRICES
mm | FOR PRINTERS AND
= APPLE Il PERIPHERALS
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PRINTERS
SMITH-CORONA TP-l..sseeee aciaeiaesiniowsunaiheel
STAR DP510, 80 column, 100 cps... ven8257
STAR DP515, 136 column, 100 cps.. ~ + £369
JUKI 6110 Daisywheel.......eeeeee s-ewrerwece ROOD
PERIPHERAL CARDS FOR APPLE II
Disk Drive..seseeeseeees - -£32.00
Colour Card + modulator. «£36.00
Language (16K).....-..-- . £39.50
80 Column..... aise D0
EPROM blower. . £48.00
Integer Basic..... ~ £34.50
Printer (Centronics).. - £38.50
BRS 2820 scsasauceaceses £41.50
Z80 CP/Mevcccccccecessevccccceees £46.50
52 Key Ascii encoded keyboard,
upper/lower CaS@.......eeeee scene £49.50
Clip-on A/C cooling fan «89.50
Centronix printer Cable.....+eee0d 9.90
All cards fully tested. Money back guarantee.
APPLE I| COMPATIBLE DISC DRIVES
Half Height Drive Model LH-1 £167.00
Full Height Drive Model AD-1 £167.00
P&P:under £ 100 add £3, over £100 NO CHARGE. Add 15% VAT
toall orders. For full details and prices of all computer consumables and
printers ring:
021-356 7402 or write to:
ROSCO LTD., Freepost, Birmingham B20 1BR.
October 1983
HARDCORE - The Journal of the British Apple Systems User Group
Page II
Mainframe Interview
The idea of using Apple computers in the
field of music isn't a new one. Most of you
will have heard of Mountain Computer Music
System, Alf boards and even Zapples! It is
therefore surprising that there have been
very few, if any, successful pop groups that
have featured the Apple in any way. Having
seen the Show Me Show on BBC | Wed 14th
September, which often features computer
items, I have a feeling that this situation
may change soon. For those of you who missed
it, the programme included a song by a band
called Mainframe, This song was accompanied
by the usual video mixing effects etc., also
by what appeared to be Apple graphics. This
would have been of interest anyway, but what
caught my attention was that the keyboard
player in the group was Herts area Basug
regular John Molloy!
To acquire more information on this
Apple-ication your intrepid reporter went
into the depths of Hemel Hempstead, to the
home ot the other band member, Murray Munro.
After a nice coffee we got down to some
questions.
Were the graphics for the TV done by the BBC
for you?
John:-"No. From the first of our concerts we
have done all our own graphics. We had
performed live 14 times before the Show Me
Show, so by then we had created graphics
worth appearing on the BBC. To be more
accurate, we either use our own routines or
use commercial sottware in our own way, Some
examples of this are Apple World,
Ceemac/Fire Organ and Graforth. We've even
used the star routine in Cyber Strike!
With the musical side of the band to
concentrate on, how do you find time to do
these routines?
John:-"Actually we have considerable help
from Colin Holgate and David Green (both
Basug members and regular Herts meeting
supporters). Colin does most of the graphics
for the shows, including the Show Me one and
David helps out if Colin is stuck for ideas,
also he is involved in special hardware
projects we are working on.
More coffee. During this break Colin
displayed some of the graphics used by
Mainframe. These included many abstract
patterns generated by the Fire Organ program
(this, and Ceemac are reviewed by John and
Colin elsewhere in this issue), sound to
light programs, 3D Mainframe logos,
ascending bubbles, Mainframe words flying
past and many other graphics effects. Some
of the sequences appeared to require several
hi-res pictures to be stored in memory at
‘once, more than there should be space for.
Colin:-"My original involvement with the
band was to help them with some graphics for
a video that accompanies the performance of
their album Tenants Of The Lattice-Work. We
needed to be able to do complex animations,
but didn't have the computer speed or film
animation facilities that the Tron creator
used. An Apple doesn't quite compete with a
Cray. This meant that any graphics had to be
in real time. Normally this means using
simpler graphics, or having 6 months to
create arcade speed machine code routines. As
we wanted to use 3D effects as well, even
machine code wasn't quick enough. Bill
Budge's 3D system is quick but doesn't
include clipping or perspective, which were
vital for our needs. The way round these
problems was to have as many complete hi-res
pictures in memory as possible and move them
into the graphics area in the right order,
using page switching to give smooth
animation. Unfortunately there is only room
for about 4 trames. By using a packing
program an average picture could be reduced
from the usual 34 sectors to about 6. When
the reduced file is loaded and unpacked into
the hi-res screen you end up with the
original picture. One of our routines shows
the Earth, then zooms into a close up of
England. These pictures were generated on
Bit-Stik, packed, loaded in sequence, and
unpacked to give the animation."
The effect is quite good, with slight
flicker noticeable. How many frames per
second is the animation?
Colin:-"On a normal Apple the unpacking
takes about 1/3 of a second, that's the
price of saving so much space. Fortunately 1
have an Accelerator, so the Earth routine
Page 12
HARDCORE - The Journal of the British Apple Systems User Group
October 1983
runs at 7,7 frames per second and uses 15
pictures, so it lasts about 2 seconds."
We then adjourned to Murray's bedroom!
Seriously. Unlike most of the bedrooms I've
seen, this one had four track recording
equipment in it. The band do their own
recording on their own record label, MC 2
(as in E equals MC squared). 1 asked Murray
if they had used the Apple for generating
music at all,
Murray:"Until the recording of the album,
apart from the graphics in our show, we had
only used the Apple computer for writing
programs that we then put onto our singles. We
do use it for storing our fan club names and
addresses using Visidex, but that's unlikely
to become a Mainframe product. The first
single we released had a short Apple text
program on it, This was a test really. To
see what response we got {rom computer users,
and to make sure that programs could be
loaded from normal records, Since we did this
two other music people have repeated the
idea on their own records. Our second single
included four programs on the B side. These
were text and sound to light programs for
the Apple, BBC, ZX Spectrum and text only
for the ZX 81. A lot of our potential
listeners have computers other than the
Apple, so we try to include as many versions
as there is time for. When we commenced the
album, we started to use one of the special
hardware devices John referred to earlier. This
is a percussion machine board that plugs
into one of the Apple slots. Dave Green
designed it and offered it to us to use on
the album, Normally we use a Moog Liberation
for our percussion sounds, but when we heard
David's board in action the Moog got locked
away!"
Murray demonstrated the sounds this board
could generate. He said that after 3 finger
clicks he would hit various things, and that
1 should close my eyes and tell him which
were real. After the clicks came a
tambourine, a snare drum, a clap and a tom
tom sound, I could see there wasn't a tom
tom in the room, so I confidently said that
the tom tom was on the Apple, and possibly
the snare drum as well, the others being
real. As you may have guessed, not only were
all the ‘test’ sounds from the Apple, the
finger clicks were too! Very impressive. |
wanted to know more.
Murray:-"There is a good chance that we may
produce these boards at a future date, so
we're keeping the methods a secret for now.
John:-"The sounds available from the board
have changed our percussion —_ sound
considerably, It's like having a cheap
Fairlight attached to the Apple."
A Fairlight, they tell me, costs about the
same price as 20 Apples.
John:-"Someday we may outgrow the graphics
ability of the Apple and go onto more
powerful machines, but not until we sell a
few albums."
Well, must help them out. I'l be down at
the record shop if you need me. John and
Colin say they'll still be coming to the
Herts meetings, between American tours that
ist
Small Ads
Sony NTSC Colour Set 13" £100
will work on Apple without colour card.
Paul Tilling. ‘fist il) ifs AeA\L
woonoo
Replay Copy Card and software £50
Ring Stuart Morley,
Office Hours ‘ty
After 6.30 i
es
neeneneee
QUOTE
"If Apple were selling no Apple IIs and no
Lisas they would still be the sixth biggest
computer selling company in the world.”
Steve Holmes
Apple Marketing Manager
October 1983
HARDCORE - The Journal of the British Apple Systems User Group
Page 13
More on the 737
by Margaret Wood
Being a relative novice in the world of the
byte and having recently had to battle with
a newly acquired Centronics 737 printer, 1
have found the tips gleaned from the back
issues of this journal to be invaluable. By
@ combination of a lot of trial and error
and a little inspired guess work, | now have
my printer doing things that only a few
weeks ago I considered to be quite
unattainable. The purpose of this article is
to indicate how I solved the problems that 1
encountered and it includes tips from
previous articles, for which I am indebted
to the authors.
I have been working with an Apple //e
processor but the solutions have been tested
on an Apple J Europlus and found to be
equally effective with one minor exception
which is mentioned below.
My printer is connected through an Apple I
Parallel Interface Card and I must say that
I found the manual to this product less than
helpful for my purpose. Firstly, there was
confusion over the correct setting for
switch SW6. Centronics 737 was not mentioned
as suitable for the OFF position although
other Centronics models were. However, the
Centronix 737 was on the list. In my
ignorance | still do not know if this is a
misprint or another model of printer. From
my programmed commands, 1 found it possible
to control the printer from cither setting. The
ON setting was a little simpler and 1 made
more progress with my later problems using
this setting so I have opted to keep switch
SW6 ON. Hidden deep in the Appendices is the
information that CTRL-I;"0" is the code to
return display to the screen, I struggled
for a long time with CTRL-I;"40N". A tip
that I found most useful was to define D$ as
CHRS(3) + CHRSG) and 15 as CHRS(13) +
CHRS9). This saves errors from omitted
RETURNs.
The next problem was to obtain an 80 column
program listing, hopefully without
extraneous symbols, 1 tried T Tse's Nice
List but it proved totally incompatible with
my Centronics 737 and, with my limited
knowledge, quite unalterable. All attempts
at controlling the printer directly through
the keyboard failed dismally. 1 could not
break through the 40 column barrier and
cryptic comments abounded at either end of
the listing. The problem was solved by
executing the following texttile with the
program in memory:
L = 66 - LEN(HS) - LEN(DS)
IF L<l THEN ? "STRINGS TOO LONG -
RE-ENTER" : END
ESS = CHRS(13) + CHRS(27)
DDS = CHRS(13) + CHRS(4)
1$ = CHRS(13) + CHRS(9) +? DDS;
"PROI"; 19; "BON"; CHRS(15); ESS;
CHRS(20); ESS; CHRS(14); HS;
CHRS(14); FOR Z = 1 TOL: 2";
2 NEXT :? CHRS(15); DS; CHRS(14);.
ESS: CHRS(15)5 ESS5 CHRS(19) © LIST
1 4 DDS; "PR#O" : END
The headings are optional and if required
should be entered direct from the keyboard
before executing the file. H$ was designed
to be the name of the program and D$ to be
the date but they can be used for any
purpose as long as their combined length
does not exceed 65 characters. The last line
is intentionally long to avoid printing a
selection of Js at either end. Although I
have not done it, I am sure that the file
could be amended and two further variables
input to give a partial listing.
A further improvement to my listings has
been achieved by the use of (CTRL-O) at the
begining of and (CTRL-N) at the end of any
important remark. The underlining obtained
is far neater than rows of asterisks and the
program is unaffected,
Finally, 1 wanted to use a Word Processing
Program and, already having access to
Applewriter 1 and Applewriter Il, wished to
avoid further outlay if possible, Applewriter
1 does run on the //e processor but some of
the rubbish that is displayed on the screen
makes it almost impossible to check and
amend certain types of text. It was
therefore not acceptable to me to use this
version with lan Trackman's Go-Between
Program. Despite scepticism from some
Page 14
HARDCORE - The Journal of the British Apple Systems User Group
October 1983
quarters, 1 find that Applewriter Il works
very nicely on a //e processor. The only
compromise to be made is acceptance of the
fact that it will not recognise my 80 Column
Card and so I am stuck with a 40 column
screen display, disappointing but _not
restricting, (Perhaps Father Christmas will
have the //e version in his sack!)
Of course my first challenge was to release
the 40 column chains. The answer to that was
laid before me in this publication so my
default constants were amended to contain a
Top Line of: (CTRL-1)132N/ . Even that took
a while to achieve. There must be no extra
spaces, no quotation marks and CTRL-I must
be entered directly from the keyboard; no
trying to be clever by entering CHRS(9)!
The next step was to investigate the use of
the CTRL-V function. First results were
disappointing. | wanted to underline. 1
could start underlining but it refused to
turn off. At this point 1 hit upon an
amendment to the Top Line command that
solved the problem, although I have no idea
as to why. The addition will work from
within the text file but it is more
convenient in the Top Line. My Top Line now
reads:
/(CTRL-1)132N(CTRL-N) (CTRL-1)
(CTRL-N) (CTRL-1) (CTRL-N)/
No less will suffice but at least it can
stay as a permanent default.
Acceptance of the remaining control codes
through CTRL-V was easy once | had tumbled
to the fact that ESC must be entered twice.
Having mastered the keystrokes required, 1
compiled a Glossary File with easily
recallable symbols for definition, The
following listing gives. the ~— actual
keystrokes to enter:
F(CTRL-V) (CTRL-3) (CTRL-V)
{Full Line Feed Forward}
1 (CTRL-V) (ESC) (ESC) (CTRL-A) (CTRL-V)
{1 Dot Space}
2(CTRL-V) (ESC) (ESC) (CTRL-B) (CTRL-V)
(2 Dot Spaces}
3(CTRL-V) (ESC) (ESC) (CTRL-C) (CTRL-V)
{3 Dot Spaces}
4(CTRL-V) (ESC) (ESC) (CTRL-D) (CTRL-V)
i4 Dot Spaces}
5(CTRL-V) (ESC) (ESC) (CTRL-E) (CTRL-V)
{5 Dot Spaces}
6(CTRL-V) (ESC) (ESC) (CTRL-F) (CTRL-V)
(6 Dot Spaces}
R(CTRL-V) (ESC) (ESC) (CTRL-3) (CTRL-V)
{Full Line Feed Reverse}
E(CTRL-V) (ESC) (ESC) (CTRL-N) (CTRL-V)
{Start Elongated Print}
e(CTRL-V) (ESC) (ESC) (CTRL-O) (CTRL-V)
{Stop Elongated Print)
p(CTRL-V) (ESC) (ESC) (CTRL-Q) (CTRL-V)
{Proportional Print}
n(CTRL-V) (ESC) (ESC) (CTRL-S) (CTRL-V)
{Normal Print}
c(CTRL-V) (ESC) (ESC) (CTRL-T) (CTRL-V)
{Condensed Print}
f£(CTRL-V) (ESC) (ESC) (CTRL-\ ) (CTRL-V)
{Half Line Feed Forward)
r(CTRL-V) (ESC) (ESC) (CTRL-~)(CTRL-V)
{Half Line Feed Reverse}
<(CTRL-V) (CTRL-O) (CTRL-V)
{Start Underline}
>(CTRL-V) (CTRL-N) (CTRL-V)
{Stop Underline}
b(CTRL-V) (CTRL-H) (CTRL-V)
{Backspace}
Because of the use of the backslash in the
command tor Half Line Feed Forward, | cannot
suggest a method of using this command with
an Apple JL Europlus unless the glossary
file can be compiled on a //e processor.
There is just one disappointment. Although |
can switch between proportional and
condensed print from within Applewriter, 1
cannot alternate between these two types and
normal print. Of course I can revert to
normal by turning the printer off and then
‘on but to switch to the other two styles |
have to use the Printer Set Up routine that
I have incorporated in the Hello Program on
my DOS disks as a pre-boot style selector.
The use of enlarged print is a little
tricky. Backspacing works but is not as I
expected. | think that it is only a matter
October 1983
HARDCORE - The Journal of the British Apple Systems User Group
Page 15
of patience and simple mathematics to reach
some formulae for its effective use. 1 hope
to submit a further article covering the
justification problems involved in the use
of these two functions.
I am not sure if novices should be writing
articles but hopefully this one may save a
little midnight oil for someone.
Exec Tip
EXEC UTILITIES
by
Martin Rogers
In my previous article, BE AN APPLE
EXECUTIVE, I promised you more applications
for the EXEC command. Here Is a useful
patch which will present you with your
program listings a page (or Screen) at a
time, Just enter the following code into an
EXEC file using your favourite Word
Processor or using a program to write the
commands to a text file called "PAGE
LISTER". Just EXEC PAGE LISTER at any time
to install, and subsequent LIST's will pause
at the bottom of the screen until you press
a key. The facility will remain active in
your machine until the next time you
re-boot.
CALL-I51
300: AY 03 AZ OB 85 37 86 36 YC EA 03 48 AD
25C9 17 FO 04 68 4C FO FD 98 48 8A 48 2C 00
CO 10 FB 2C 10CO 20 58 FC 68 AA 68 AB 68 4C
FO FD
3D0G
HOME:VTAB5:HTAB9:?"Page Lister Installed
VTAB12::2"All Listings will now display a
page at a time until you re-boot the System.":
VTABZItH TABI L:?"AnM.C.R. Utility.":VTAB23:
HTAB10:?"Any key to continue."
CALL768
Watch this space for more exciting
utilities! Even better, write in with any
that you have developed which you would like
to share with BASUG members.
Education
by Norah Arnold
FOUR NEW BOOKS ON LOGO
AND TURTLE GRAPHICS
Three of these books are about Logo and one
is a little different in that it deals with
turtle-graphics only. 1 shall discuss that
‘one first and then deal with the Logo books.
PICTURE THIS TOO!
subtitled An Introduction to Computer
Graphics for Kids of all Ages.
Author David Thornburg.
Published by Addison-Wesley, 1982.
Price £9.00.
This book is fairly large, spirally bound,
with an attractive cover. On first opening
the book one gets the impression of well
presented material, clearly set out and
containing many black == and_—s white
illustrations of the computer screen, There
are versions of the book for other machines
but the version I have used is written tor
those who have access to an Apple II with
the language Super-Pilot, an extended
version of Pilot incorporating _ turtle-
graphics.
According to the author the book is aimed at
‘kids! of all ages. 1 think that an
intelligent nine year old could cope with
working through this book with a bit of help
here and there with the vocabulary. Equally
well an adult new to Super-Pilot and
turtle-graphics would find this a good book
to begin with. One thing that children seem
to like about the book is its ‘chatty’ style
with a good spattering of Aha! Whoops!
Ta-Daal Wow! and other phrases terminating
in exclamation marks. I can imagine some
older people might find this style a little
irksome.
1 think that it is fair to say that this
book is written in the immediate mode. By
this I mean that it follows the pattern of
1. Let's type this. 2. Here is a picture of
the screen, 3, This is what happened and
Now let's proceed by doing
throughout the book. —_—This
inevitably means that progress through the
actual turtle-graphics material is slow but
done in a reasonably detailed manner. Very
simple drawings of lines and squares are
Page 16
HARDCORE - The Journal of the British Apple Systems User Group
October 1983
dealt with in Chapters Four and Five. In
Chapter Six you learn to draw a stick figure
of a person and not until Chapter Eleven do
you learn to draw curves and circles. The
last chapter, number twelve, ends with a
simple drawing of a flower.
The content of the book does not actually
take you very far into the realms of
turtle-graphics but over the distance it
docs take you it holds your hand all the
way. So if you are a whiz-kid just starting
on Super-Pilot who wants to be doing
marvellous lace-like turtle-graphics designs
in a matter of hours then this book may not
be for you. On the other hand, if you like a
lot of help and encouragement and don't mind
going slowly and surely through the material
then this book would be a good buy. That is,
providing you have Super-Pilot which |
rather suspect that not many people have.
LEARNING LOGO ON THE APPLE II
Authors Anne McDougall, Tony Adams and
Pauline Adams,
Published by Prentice Hall of Australia, 1982.
Price £11.00,
This book is aimed at people who know little
of computing but who wish to use Logo, In
view of this it starts with an explanation
of how to set up the system and get going
and then describes how it intends to deal
with the differences between the two
versions of Logo for the Apple Il, that is,
M.LT. Logo (Terrapin and Krell) on one hand
and Apple Logo on the other. When program
listings or single procedures are given then
the two versions are printed side by side,
with M.I.T, Logo on the left and Apple Logo
‘on the right. I found this approach far more
satisfactory than the differences being
shown only in an Appendix. Clear
sub-headings to the chapters help you to
find things easily and in general the
presentation of the material is good.
Although this book may appeal to some
teachers or parents who wish to interest
their pupils or offspring in Logo
programming, no help is given over the
approach which should be used in presenting
the material to the younger generation. For
instance, in describing the ‘total turtle
trip' theorem, a table is given of the
number of degrees necessary to produce
triangles, squares, pentagons, hexagons etc.
This, however, is precisely the kind of
thing that a child should be encouraged to
discover through experiment rather than
having the list given a foregone
conclusion. One good point is that exercises
giving suggestions for further work are
given at appropriate points throughout the
book.
The book does cover the basics of Logo well
enough to enable a newcomer to the language
to carry out their own projects in
turtle-graphics including — those —_—_using
recursion, One chapter deals with the
arithmetic one can do with Logo, again in a
reasonably simple manner. Some of the most
interesting material in the book appears in
the last three chapters on list processing.
The authors of this book appear to have had
sufficient involvement with Logo on the
Apple Il to know of some of the little
pitfalls and problems which can arise. However,
fone thing that worries me is that most of
the points covered by this book are dealt
with equally thoroughly in the Logo manuals
for Terrapin and Apple Logo. 1 can say
nothing about, the Krell manuals as I do not
possess them. If you own the Terrapin or
Apple manuals then to buy this book would be
unnecessary in my opinion, If you are in a
group situation where access to manuals is
limited then a copy of this book would be
extremely useful.
LEARNING WITH LOGO
Author Daniel Watt.
Published by McGraw-Hill, 1983
Price 16.50.
1 had been awaiting the publication of this
book with interest for some time. Daniel
Watt worked with the Logo Group at M.LT. for
five years as an educational researcher and
has had a great deal of experience in
teaching Logo to adults and children.
It is a large book, approximately 11 x 9
inches and weighing almost two pounds. It
has soft covers and is spirally bound. A
great deal of thought has gone into the way
the material is presented in this book. The
book is divided into three parts. Chapters |
to 6 are for children between the ages of
ten and thirteen to read and work through
themselves, although personally 1 would
think that intelligent eight to nine year
olds could be included here if they were
proficient at reading. Chapters 7 to 9 could
be worked through by any child who has
satisfactorily completed Part 1, who has
understood the concepts involved and had
time to experiment and practise using them, The
October 1983
HARDCORE - The Journal of the British Apple Systems User Group
Page 17
rest of the book, Chapters 10 to 14 is meant
for youngsters from 13 or 14 upwards or for
children younger than this to work through
with an adult to give a hand here and there.
Much effort has gone into making the book
attractive to children, for instance the
trickier concepts are explained with the
help of cartoon characters; the turtle
himself, the Logo wizard and Logo's helpers
who are shown as robots whose tasks are
linked to the shape of their heads. 1 could
imagine most children would be grabbing for
their crayons and felt-tips to colour the
cartoon characters when they take a break
from seriously perusing the content of the
book,
The left hand margin of the book is used to
display cartoon symbols indicating ‘powerful
ideast (ie. important concepts),
‘exploration’ sections giving ideas for
further experimentation with a concept and
finally ‘helper's hint’ sections which are
given in smaller print and are directed at
any adult, teacher or parent, who is working
with the child,
This book is directed mainly at users of the
Terrapin and Krell versions of Logo for the
Apple. However, pages 289 to 358 are given
over to appendices covering several subjects
including using the book with Apple or TI
Logo,
Ido have several criticisms of this book. First,
I found it rather floppy and difficult to
handle because of its size, weight and soft
covers. A child using it would need to have
enough table surface next to the computer to
support the book as it is far too heavy and
floppy for a child to hold. This raises the
question as to whether a slightly less
extravagant format with smaller symbols and
cartoons would have led to a book which was
easier to handle and therefore more pleasant
to use - a debatable point. Secondly,
although no-one can dispute Daniel Watt's
high degree of involvement with Logo over
many years, 1 was disappointed that so much
of the content, although presented in a
highly original way, echoed material already
published by other members of the M.I.T. Logo
Group. Thirdly, I was sad that the price
will put the book out of reach of many
primary school teachers in this country,
whose capitation allowances might run to one
copy being purchased for reference, but
would certainly not allow a reasonable
number to be bought for use by the children.
Having <aid all this, if you want your
children to enjoy becoming proficient at
Logo, you could not do better at the moment
than to buy this book and enjoy using it
together.
LOGO PROGRAMMING
Author Peter Ross
Published by Addison-Wesley, 1983
Price £7.95,
I had been using my own copy of this book
for several weeks before the review copy
arrived. It is different from the previous
two in that it is ‘home grown’ and
originates from the work of the Logo group
in the Department of Artificial Intelligence
at the University of Edinburgh. It is also
different in that it does not have a picture
of a hand placing a disk in a drive. In
other words it is not a book for complete
beginners to computing and it is not aimed
at children, Neither does it cover the same
material as the manuals which come with the
different versions of Logo. Although
Terrapin Logo is used throughout the book,
notes are given on other versions where this
is necessary. Appendices cover Apple Logo,
Research Machines Logo for the 380Z, TI Logo
for the TI99/4 and 4a, and Radio Shack Logo
for the Tandy 32K Color Computer.
The content is presented in a straightforward
and scholarly fashion and takes you into
Logo at a fairly rapid speed. There are some
good technical points. made and I
particularly liked the section on the
problems of animation in Chapter 3.
Suggestions for further exercises are given
at appropriate points within the text and
where necessary answers are given in
Appendix F.
This book would not be suitable for anyone
who just wants a superficial knowledge of
Logo in order to play around with the
graphics. It seems suitable for anyone who
is conversant with their machine, who has
some knowledge of other languages and who
wishes to be able to program efficiently in
Logo. It would probably be a suitable book
for teachers in Computing Departments in
secondary schools.
Criticisms? Well, it is a bit wordy in
places and perhaps there could have been a
few more illustrations, but I have found it
accurate and a worthwhile buy at the price.
IN CONCLUSION I am still waiting for a book
on Logo which is directed at parents and
teachers and which shows the numerous ways
(continued on page 19)
Page 18
HARDCORE - The Journal of the British Apple Systems User Group
October 1983
Says Jane Davis:
66NIOW
you can
dione
MICROPRO”
with the 444
At last, an easy to read, simple to under-
stand book - written in plain English
for British users of MicroPro software.
Giving you the full power of:
Wordstar MailMerge” SpellStar™
‘DataStar ". SuperSort ”. CalcStar
‘© EXISTING USERS - EVER HAD PROBLEMS?
Let Jane Davis’ tutorial method be your guide
‘* NEW USERS? In Part 1, you will master your operat
ing system; create a tutorial disc and produce
merge - printed leters ond envelopes - all within
two days!
The ProStar Training Guide is unique in
covering all six MicroPro packages in
ONEVOLUME* ejyefualing
wr Report Star
Whether you have ONE
MicroPro package —
or SIX—this is the
guide for you
1 To: rab bagel fee ag
38 Ehelden Road, London W12 78
4 Please send me.. -x.-copies of the
1 ProStar Training Guide ci £29 per copy induding
1 postage ond pucking.
Allow 3 weeks tor delivery Make cheques payable lo: Jone Dows
T pnicotone
1 Preose send me hither information |]
! NAME
1 ADDRESS 1
1 !
1 !
Coo
Book Review
Title : ProStar Training Guide.
Author: Jane Davis
Price : £29.00 inc p&p.
Published by JD Publications, 38 Ethelden Road,
London W12 7BG.
A Review by Jim Panks.
Manuals on software are cither good, bad or
indifferent, Jane Davis has decided to sit
down and make the MicroPro range of software
much easier to understand by writing an easy
to understand manual, The manual contains
all you need to know on the following
packages : Wordstar, Spellstar, Datastar,
Calcstar, Mailmerge and Supersort.
The manual adopts the tutorial form of
learning, with all steps being explained
down to the last detail, no over technical
words have been used and the book is aimed
directly at the user who wishes to get on
and use his software. The ability to link
the various packages has been explained and
although this may sound daunting, this
manual does the job in an excellent fashion.
The first chapter contains the general CP/M
copying and setup data to enable you to go
on to chapter two where making back-ups,
tutorial disks and the printing of files are
discussed.
The next chapter is devoted to Wordstar and
goes through all the basic commands
explaining how to enter data, store files
and print documents. 1 found the style very
pleasing, by the end of the chapter I was
using Wordstar with confidence.
The following chapters in section one
explain the DataStar and Mailmerge packages.
The basics are covered well and help you to
understand the ways in which you can put the
packages to use.
Section two covers all the packages and
takes you in depth through all the more
advanced features. The — interlinking of
packages is explained in great detail, but
still does not overwhelm the user. Many
useful tips are given, and from this a good
working relationship with the software can
be obtained,
There is a glossary of terms to round off
this excellent manual.
October 1983
HARDCORE - The Journal of the British Apple Systems User Group
Page 19
The price is very reasonable and is value
for money. The manual comes in A4 size and
the 200 pages are placed in a strong ring
binder. The manual has large type with bold
letters being used to emphasise user input;
each page has been laid out so that the page
is uncluttered and easy to read} the layout
has been designed with thought. There is a
very comprehensive index.
This book is ideal as a reference manual
after the tutorial has been completed. It is
anticipated that all the packages could be
learnt in three weeks, this time scale
assumes that you split the lessons up into
two or three hour stints. 1 think that this
is a reasonable time scale. This will
probably suit the user in an office
enviroment where a chapter a day in between
other work would not interfere with normal
routine.
I would recommend this manual to any user of
Micropro Software, the author has devoted
her wide knowledge of this software to
produce one of the best software manuals 1
have seen. Maybe the software publishers
will take heed and make manuals to this
standard.
Lonely Apples
The following member would like to contact
others in his are
J. Howard Wright
it?
2A
wate
Ctepiten
iFieiety HER
Tel: Alloa wilt) 213%
Education
cont.
in which Logo projects can be linked with
the rest of the school curriculum. After
all, why program in Logo once you know how
unless the programs can be shown to have a
usefulness In the general process of
education,
Fast Circles
by Ray Harris
Do you tire of plotting circles so slowly
that you can count the points as they
appear?
Here is a small set of programs that will at
least keep you awake, although 1 don't
guarantee that they are the fastest
possible. Circles are plotted at the rate of
10 in about 3 seconds. | am grateful to
Derek Ball of Leicester University School of
Education for the basic idea, suggested tor
the RML 380Z.
The centre of a circle may be anywhere
within the screen boundary, and the radius
from 1 up to well over half the screen
width. I wrote the programs for the ITT
2020, which involves some scaling to create
a true circle, as does my printer. You may
enter your own required scale factor in the
'Circle Creator’ program. To adapt the code
for the Apple requires only two changes to
the hex listing, both noted. Relocating the
code will require just one change, in line
You should enter the hex from $94E0 to $99D>
and BSAVE CIRCLE.B,AS94E0,LSF6. Next RUN
CIRCLE SETUP, which will write data from
$9400 to $949F (the coordinates of points on
one eighth of a circle of radius 128 units)
and then save the whole memory from $9400 to
S95FF as 'CIRCLE.M/C'. Only 'CIRCLE
CREATOR! is required in future for producing
circles, together with the new hex program,
‘CIRCLE CREATOR! has no built in error
checking, because you are likely to adapt it
for your own purposes. However, there is
nothing wrong with drawing a circle which
goes partly off the screen: that part will
not be plotted.
In drawing each circle, with the flag
holding 0, the sections | to 4 are plotted,
each point in | being followed by its images
in sections 2, 3 and 4. When the flag holds
1 sections 5 to 8 are plotted similarly. The
two plotting halves correspond effectively
to different radii in the X and Y coordinate
directions, so changing SC will produce
ellipses. See what you can do with it!
Page 20 HARDCORE - The Journal of the British Apple Systems User Group October 1983
Ren renee
AEH = + CCIRCLE SETUP #
REN tt ORAY HARRIS.
80 FORT = 01079
90 X= COS(I / 100)e128Y = SINCI / 1000128
100.1= INT (1+ 0,5) = INT LY + 0.5)
110 POKE AD,I: POKE AD + 1,¥
120 AD = AD + 2
130 NEXT I
140 DS = CHES (4)
$80 PRINT DS*BLOAD CIRCLE.B*
160 PRINT DS*BSAVE CIRCLE.M/C,A$9400,L4200"
10 REN ‘Veeeeseneeeeneeeenes
20 REN + CIRCLE CREATOR #
30 OREN '
40 REN eeneen
50 HIME: 37888
60 PRINT CHRS (4)*BLOAD CIRCLE. M/C
7 POKE 235,0 POKE 236,148: REM BASE IN SEB.EC
80 CIRCLE = 38L12:FLAG = 6
90 TEXT : HORE
100 SC = 96 / 79: REN SCALING FACTOR FOR ITT & AY
‘RONITOR
110 REN FOR APPLE SC IS CLOSE 10 15 CHANGE SC
FOR SOME PRINTERS
120 INPUT "WHAT POINT IS THE CENTRE?(1,' Y
130 POKE 227,Ys PORE 23741 ~ 2566 IMT UT /
756); POKE 238, INT (1 / 256)
140 PRINT
150 PRINT “WHAT IS THE RADIUS? (<* INT (255 /
SC)*) “2 INPUT **5R
160 HGR2 : HCOLORs 3:R1 = R # SC
170 PONE 213,R1s POKE 215,R
180 POKE FLAG,O: CALL CIRCLE: REM LEFT & RIGHT
190 POKE 213,R: POKE 215,R1
200 POKE FLAG,1; CALL CIRCLE: REM TOP & BOTTOM
210 REM TO RUN AGAIN TYPE "RUN 80°
EO: 48
HEIs AO 00
‘WES; BL EB
945: 85:19
9407; AS OS
WER: 85 IF
yee: AS D7
‘MED: 65 FF
AEF: AF 00
OF As BS 1A
‘94F3; 85 1B
‘W452 85 IC
‘94F7: 85 1D
FS: 85 1E
94 B: 85 FB
‘94FD: OS FC
S4FF: 85 FD
95012 AZ 08
9503; 46 IF
9515: 06 19
9517: 26 1A
9519: CA
951A: DO EF
Pitti
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' CIRCLES .
' 1
' RAY HARRIS. .
' ’
' 5/7/83 .
'
PUNE THerereeeeeneneaeenney
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xeouRd = $19
PRODUCT = S18
XOFFSET = $10
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RISTORE = $05
RsTORE = ($07
YEENTRE = $83
BASE = NEB
XCENTRE = 98D
YSTORE = SEF
yeoord = $F9
YeroDuct = $B
YORRSET = SD
Tero = OFF
HPLOT = (S498,
.
HHPLOT 18 $F498 for ITT and $F457 for APPLE
'
ORG $9460
PHA
Loy £800
SETX «LDA (BASED,
sta 1c00RD
(DA RISTORE
‘STA TENPL
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‘STA TEMPO
Lr £900
ST@ XCOORDE
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STA XPRODUCT#!
STA NOFFSET
STA XOFFSET#1
STA YPRODUCT
STA YRODUCT#1
STA YOFFSET
tor £808 sto count shifts
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STA xPRODUCT
LDA XCOORDE1
ADC XPRODUCT+
STA XPRODUCT#S
TLEFT ASL COORD
ROL XCOORDS1
ANE NULTRY
October 1983 HARDCORE - The Journal of the British Apple Systems User Group Page 21
9510: 06 1B bb ASL XPRODUCT
SIE: 26 1C 7 ROL XPRODUCT#I 957E: C9 00129 CHP f9c0
9520; AS AC 68 LDA xPRoDUCTes 9580: BO 0S 130 BCS PLOT2 §— iY coord?191
oe 9582: 20 98 FA 131 JSR HPLOT
70 Suse the high byte to effect the division 9585; 18 132 PLOT2 CLE
no 9586: AS ED 133 LDA XCENTRE
9922: 85 1D 72 STA YOFFSET 9888: 65 1D 134 ‘ADC OFFSET
952; 8B NY 958A: AA 135 TAL
9525: BL ER 74 GETY LDA (BASE, jdo the sane for Y 9988! AS IE 154 UDR XOFFSET+I
9527: 5 F975 Sia YouORD 9800: 8S EE 137 ADC ICENTRES
9529: #900 7B LDA £400 958F: 8 138 TAY
9928: 85 FA 17 STA YCOORDe! 9990: 38189 sec
9520: A208 78 LOK £808 95915 AS E3140 LDA YCENTRE
952F: 40 FF «79 MULTR «LSR TEMPO 9993: ES FD 1a SHC YOFFSET
951: 90 0E 80 BCC YLEFT 9595: 90 03 142 BEC PLOTS «3140
9533; 18 we 9597; 20 98 FA 143 452 HPLOT
954: AS FP 82 Ua YeoORD 144 PLOTS. SEC
953: G5 FR 83. ‘ADE YPRODUCT MS LDA CENTRE
9538; OS FB OF STA YPRODUCT 4b S8C_ XOFFSET
953A: AS FA 8S Loa YeoORDe 147 Tat
9830 6S FC 8b ADC YPRODUCTS1 140 LDA XCENTREH
2 OFC 87 STA YPRODUCTS1 ua SBC XOFFSET+1
1 ae 150 BAL NENT 3100
0679 07 YLEFT ASL YCOORD 151 ww
0 ROL YCOORDeA 182 ac
on Der 183 LOA YOENTRE
n BRE MULTR 1 ADC YOFFSET
% SL YPROBUCT 155 BES PLOTA 399255
4 ROL YPRODUCTS} 156 CHP £900
% WDA YPRODUCT 177 BES PLOTA = GYDI9
% STA YOFFSET 158 ASR HPLOT
” ST YSTORE 159 PLOTA SEC
% LDA FLAB 160 LOA XCENTRE
8 REQ PLOT 161 SBC XOFFSET
100 LOA OFFSET 162 Ta
101 LOK YOFFSET 185 DA XCENTRES
402 STA YOFFSET 164 SBC XOFFSET#
103 STA OFFSET 165 Tat
108 toa £800 166 sec
105 STA XOFFSET+ 9501: AS ES 167 UWA YOENTRE
10 8 9503: ES FD 168 SBC YOFFSET
107 HPLOT needs I-coordinate in reg.¥, 1 9505: 9003 189 BCC NEAT 5100
108 tand Y-coordinate in req.A 9907: 20 98 FA 170 JSR HPLOT
109 + sch: a4 EF 171 NEXT LOY” YSTORE
18 110 PLOT «cue 980Cs 08 172 INY
AS ED Mt UDA CENTRE 950; CORD 173 cry £4K0
51D 112 ADC XOFFSET m+
3 AA 113 TAX 175 #00 points, 2 bytes per point
ASE 14 LDA XOFFSET+1 me +
SEE 11S ADC ICENTRE+ 5cF BOOS 377 RES END
FOO 116 REO x0K sH-coord (256 SDI: AC ES 94 178 oNP GETE
20902 MT CHP £902 9504: 68 179 EMD PLA
2 8 BCS PLOTS #511 95051 60 180 RIS
3 E068 119 OPK £868
120 ¢
421 #(£868 for ITT, £618 for APPLE) =-End asseably--
me
95742 BO 24 123 BES PLOTS 319359 or 279 246 bytes
95761 AB 124 0K TAY
95775 18 125 ce Errors: 0
9578: AS ES 124 LOA YCENTRE
957A: OS FD 427 ADC YOFFSET
957: BOOT 128 BES PLOT2 $Y coord 255
Page 22
HARDCORE - The Journal of the British Apple Systems User Group
October 1983
Permanent & Temporary Strings
IN BASIC OR
HOW TO AVOID GARBAGE COLLECTION
by Richard Teed
Garbage collection is something that seldom
bothers a user of BASIC: this is because
memory generally takes a lot of time to
become exhausted, but when it does and a
garbage collection is invoked then the
computer may hang-up for about five minutes
and | believe the theoretical limit is
somewhere in the region of four hours!
If one thinks about it, it is possible to
extract enough information from a program to
tell BASIC when and where to garbage collect
so that a full scale garbage collection is
not necessary, The problem is that no
facilities exist at a high level to make
this possible.
Programs that use strings fall into two
groups when creating strings: the first is
Constantly creating temporary strings as in
copying one file to another, and the second
has a number of permanent strings from which
temporary strings or further permanent
strings are created.
Let us examine how to avoid garbage
collection on the two classes of strings,
but first here is.a memory map of BASIC's
variable space to make the explanation
easier:
(HIMEM)
-start of string storage
strings build down from
1 (HIMEM)
V_ bottom of string storage
teeceee stop of array storage
!
arrays!
teceee- +bottom of array storage
H
Isimple!
tvaria-!
‘bles !
1 1
start of simple variables
(LOMEM)
What causes a garbage collection is when
there are so many strings that they have
come down from HIMEM and are about to
over-write the array section of memory, the
interpreter then sees which strings can no
longer be accessed and removes them moving
valid strings up to take their place.
Consider the following program and suppose
that "A$" and "BS" are to be permanent (by
permanent I mean available to the program
throughout its execution), while the value
assigned to "C$" is temporary; that is it is
only valid within the subroutine after which
its value may be lost:-
100 AS="ONE" : BS="TWO" : C$=AS+BS :
GOSUB 1000 : C' $+A$ :GOSUB 1000 :
C$=AS+A$ : GOSUB 1000 : END
1000 PRINT C$ : RETURN
The first. two _ statements
the following strings in memory:-
+--+ HIMEM
fea
!
!
produce
ozm
/
'
!
40!
!
!
+
!
!
!
After the third statement the memory looks
Vike thi
+---+ HIMEM
! STRING 1
!
! STRING 2
t
STRING 3
| Ozm4401 440! O2m
October 1983
HARDCORE - The Journal of the British Apple Systems User Group
Page 23
After the fifth statement however things
look like this:-
boone
Ee!
1! .N 1} STRING L
1o!
peoet
1o!
1 Wo! STRING 2
ie oe |
er
1ot
tw
1 T 1 STRING 3
te!
tn!
ot
tenet
te!
tal
10 ! STRING 4
1ol
twi
1T!
boone
STRING 3 will no longer be accessable and
would be cleared by a garbage collection.
In order to make string "A$" and "BS"
permanent and string "C$" temporary a little
code must be added to the subroutine and
just after all permanent strings have been
created.
What needs to be known is the memory
location at which the permanent strings stop
and this is given in locations $6F and $70
(111 and 112), Now each time before exiting
from the subroutine (any temporary strings
having being finished with) we must put the
bottom of string storage back to the bottom
of the permanent strings so that the next
temporary string overwrites the last. Here
then is the complete program:
100 A$-"ONE" : BS="TWO" : PL=PEEK(II1) +
PH=PEEK(112)
110 C$=A$+B$ : GOSUB 1000 : C$=BS+A$ +
GOSUB 1000 : C$=A$+A$ : GOSUB 1000 :
END
1000 PRINT C$ : POKE I11,PL : POKE 112,PH
:RETURN
The constant re-setting of the bottom of
string storage means that it will never
reach the top of array storage which would
cause a garbage collection.
You can of course update the number of
permanent strings simply be PEEKing location
111 and 112 just after the new permanent
strings have been made.
Modifying BASIC's pointers like this can be
dangerous if you are not careful, but
basically the only thing that you should not
do is to produce a new string from temporary
strings that have just been released by
re-setting location 111 and 112, because the
new string will be created over the top of
the strings that are to comprise it
resulting in corruption,
Software Library
I have not received one program for
inclusion in the software library since the
last magazine in August. I would hope that
this is due to holidays etc,
1 would ask anyone with material that they
think may help other people or would be
suitable for the software library,
especially Pascal, CP/M or programs for the
younger user (Christmas is fast approaching),
to send it in as soon as possible so that I
can realease some more disks into the
library. It's all up to you!
1 will be writing to all those that have
helped in the past to see if they are still
willing to do the same work in the future.
There is much work that needs to be done in
respect of updating the software library to
3.3. DOS.
Our new Special Software is ready with
Business Basic by Richard Teed, GR Pad by
Mike Siggins and four programs by lan
‘Trackman, These are really good value and
come complete with a manual, So send your
orders in. The programs cost £11.50 each.
Last but not least, we are still looking for
good quality program material for our
Special Software Library. If you think that
you have anything, please contact me for
details of the standards we expect. Remember
we pay for these.
Page 24 HARDCORE - The Journal of the British Apple Systems User Group October 1983
LOOK! ... FOR ALL YOUR @ pple Ac
CONTACT THE FRIENDLY
ms fully guaranteed for one year @ Immediate delivery @ Free postage and packing
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80 COLUMN CAROS & ACCESSORIES
STROBE GRAPHICS PLOTTER
Create super hardcopy graphics directly
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ROSETTA
THE BIT STIK Rosetta is a utility t
GRAPHICS SYSTEM DOS and ‘vice
Price £185 plus
VAT
AVAILABLE DIRECT FROM [BAGE OR FROM YOUR LOCAL APPLE DEALER
October 1983 HARDCORE - The Journal of the British Apple Systems User Group Page 25
CESSORIES PACE
pr ner STA se ib 0274 729906
Ten Sin ap shen seinen
papery on seeds
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Page 26
HARDCORE - The Journal of the British Apple systems User Group
October 1955
Communications Update
by Q. REIDFORD
Following articles in the previous two
issues of ‘HARDCORE! and with the knowledge
of two months use of 'MICRONET' I feel that
it is time to put my experiences to BASUG
members and poll their reactions.
As I see it there are two roads that we as a
group can go down;
A) Micronet, via Prestel
B) Bulletin boards and data exchange similar
to 'The Source’
A. PRESTEL (Micronet)
This system uses a Modem linked to the Apple
via an RS232 interface to recieve data at
1a Baud and transmit at 75 Baud. The
jal cost of the HARDWARE is £75.00
(special offer to BASUG) plus Prestel fee of
£5.00 per quarter plus the Micronet fee.
The Modem for the Apple will be a direct
connect version with a switchable Baud rate
of either 1250/75 OR 1200/1200, however the
1200/1200 baud rate is HALF-DUPLEX i.e. if
two people are communicating then one must
agree to be the sender and the other the
recipient. This protocol is set by the use
of a switch on the modem, software switching
will come, but | am unsure whether it can be
envoked without disconnecting.
The most important aspect however has got to
be the content, the information to be
gleaned or exchanged. Prestel has an
extremely good service called 'Viewfax'
which has Micro-news, software, and gossip. It
is well laid out and interesting, and although
it is not Apple specific, this ‘magazine’
could be emulated to a great extent by BASUG
on our own pages.
Software that is available is either free or
relatively cheap (BBC), however I have found
that a lot of the programs are poor quality
(free ones!!) and can take a long time to
down-load, particularly if the built-in
checksums don't and the page in question has
to be taken down a second or third time -
however that
of itt!
is all part of the initial fun
Letters which are sent in to the magazine
are put up on a ‘bulletin board' as are the
answers, but this interaction is only as
good as the management of the magazi
Information on club events and meetings are
available as are dates for computer shows
etc, The gossip section of Viewfax,
rejoicing under the name ‘'Micrognome', is
both interesting and fairly uncompromising.
However there are several problems that I
feel members should be aware of and
depending on their requirements, consider
carefully before parting with their cash.
1, Telephone costs can become very high,
particularly if your nearest —_Prestel
computer is not a local call, mine isn't..!
2. Telephone line noise can be very
troublesome, again if you have to use
long-distance. This will be helped by using
the direct connect modems. The acoustic
version is distracted by kids shouting and
requires care in positioning the handset.
3. Unless you live in the Lond
cannot use the ‘'Mailbox' facility to any
great advantage. The local computers only
hold one message at a time and do not
transmit that message to the other
computers. I cannot send a message to a
Prestel user unless he is registered on the
same computer, OR I call London....Bad lines
ete,
area, you
4, Particular Prestel facilities such as
colour and graphics, while attractive, are
not essential’ in transferring information,
programs etc. But they are a nightmare to
produce and take precious time to transmit.
5. Unless you particularly want to know what
films Quantas are showing on their long-haul
flights, or you frequently book theatre
seats or hotels/flights, you will tend to
use the system to collect 'mail', with
perhaps a quick excursion to particular
pages of interest.
October 1983
HARDCORE - The Journal of the British Apple Systems User Group
Page 27
B. BULLETIN BOARDS.
These are public access data bases which are
run by enthusiasts such as ourselves. They
use a standard 300 baud FULL-DUPLEX modem
connected via an RS232 interface,
1 know of seven of these bulletin boards and
have accessed four of them using a borrowed
Modem, Apple communications card, and a
standard communications package. I believe
that all these data-bases are run with
TRS-80 computers with about 200K disk
storage. I understand that the Tandy is used
because of the host software, bought in the
States, but there is little, apart from the
Auto-answer modems, that many BASUG
members do not already have.
The principal feature of this type of
data-base is the ability to leave messages,
either to a particular person, or as an open
letter, for example asking for help.
There is also a section for down-loading
programs, mainly communications, and mainly
for TRS-80, Apple takes a back seat.!!
However the programs that I have taken down
for a BBC using the Apple seemed worthwhile,
and free.
There are SIG pages and sales and wants, all
good stuff, and easy to access.
A feature which is particularly friendly is
the ‘chat’ mode. In this mode, if the system
operator is near his machine he can break in
for a chat, on request, and help out
immediately with information or whatever.
Interaction and direct communications are
very much more enjoyable than the passive
role of Prestel.
The Bulletin-boards can emulate any terminal
and you configure the system on initial
entry by answering a few questions about
screen width etc. You then choose a password
and from then on you will get messages etc. on
signing on and of course the system will
remember your terminal configuration.
It is particularly nice to see a few users
from Finland and Denmark using the system. In
the Hull Bulletin board there are many
callers from the States, which makes it VERY
interesting.
For those members with access to the
necessary equipment, here are some numbers
and instructions:
L.Liverpool (24 hours) 051-628-8924
This is an auto-answer system,
If using an Apple press return when
asked for terminal type.
2.Hull (9pm-Lam) 0482-859169
I get a poor line so access limited,
but it's the most interesting,
3,North-East (9pm-lam)
4.Stourport ( 27? )
5.London (8pm-lam)
0207-43555
"0299-32853
*01-348-6518
* Dial number, allow 2 rings, hang up and
re-dial for connection to computer.
All systems are 300 Baud, 7 bit even +1
parity.
PROBLEMS:
1, Phone costs still high, but
better.
2, No Apple users, yet.
information
My own view is that there ismuch more scope
for the bulletin board approach to
communications, than the Prestel/Micronet
route. The Apple has a wealth of commercial
hardware and software for 300 baud
data-bases, there are many articles on the
subject in American magazines, and as we are
all using the same machine we can happily
exchange information Modem to Modem with
each other without an intermediate stage.
I want to be able to look through messages
and problems, make contact with other
members, exchange programs etc, etc.
IT do not believe that Micronet can
adequately provide this service, particularly
as it depends on intermediate editing. Members
will pay, through Prestel, for a service
that they may never use, and unless they
really want to USE Prestel then I believe
that BASUG should look to the interactive
300 Baud bulletin board.
In terms of hardware and costs, we know that
the Micronet package will give us basic
communications as already described, for
£75.00
Page 28
HARDCORE - The Journal of the British Apple Systems User Group
October 1983
What I would propose is that members would
buy a freely available modem kit from MAPLIN
at £39.95 and a serial card such as an RS
232 interface. The Maplin modem does NOT
have BT type approval, although it will
comply when the wheels grind into motion:
Many people use them and they are reputed to
be excellent.
The main problem is that it comes as a kit,
‘on top of this you must know something about
electronics to get it to work. I certainly
could not build one without help, and |
imagine that I am not alone II!
However it sufficient people were interested
we would hold a series of regional or local
seminars where members could come for the
day, armed with a soldering iron, and, under
the’ guidance of an expert, build their own -
assuming known numbers we could even arrange
for the kits to be available for purchase at
the seminar.
With the communications card we have the
problem of cost again, the Apple comms. card
costs about £100 and that's a lot!
Hardware designers, here. is_-—_-your
opportunity! Can we please have some-one
offer their services (paid!) to design a
basic 300 Baud comms. card. This could be
available either as a kit or as a built
unit, and if the cost could be kept down to
around £30.00 then the whole package of
Modem/card would be in the same ball-park as
the Micronet offer.
On the telephone costs aspect then I think
that we may well have a network of
volunteers throughout the Country dedicating
their machines (probably on a rota). BASUG
would supply the software and all you would
have to do, if the modem was auto-answer,
would be to leave your machine switched on
for a few hours in the evening.
I would think it essential that BASUG had a
central data-base, auto-answer, 24 hour
service which would be the principal point
of reference. This central system could
contain chunks of the software library,
ordering service and help’ centre.
It is essential if we are to continue with
this excercise that we can get an accurate
indication of our members wishes and
therefore I would appreciate it if
every-one could send answers to the
following questions as soon as possible so
that we can then arrange either that the
Micronet connection is enhanced OR that we
organise the kits, software and hardware to
get our own Bulletin-board under way without
delay.
COMMUNICATIONS SURVEY:
1. Are you intereseted in using your system
for communications?
2. Are you interested
MICRONET system?
in purchasing the
3. Are you interested in purchasing a 300
Baud system?
4, Would you wish to attend a construction
seminar?
To assist in arranging suitable seminar
centres could you please give your address
and telephone number.
If you can contribute either in software or
hardware design please include details.
There is NO obligation to purchase anything
by answering these questions.
We have already had a very good response to
the extract from Quentin's article that
appeared in the Update. Here are some quotes
to give you an idea of what has been said so
far.
Tony Game of Felixstowe, Suffolk.
I am very much concerned with the whole
subject as owing to a disability which
prevents me from travelling much, I have
been unable to partake in the affairs of
BASUG as much as I would have wished. I see
responsive and versatile communications
system as being very much the answer to
this.
I heartily agree with you that a system
whereby one has to establish a verbal
October 1983
HARDCORE - The Journal of the British Apple Systems User Group
Page 29
contact before sending anything is far from
ideal. It seems to me that if the Call Apple
style of hotline is to be established it
could most easily be done via an Apple
somewhere being available to record a
problem or request, the answer when possible
being sent back to the waiting Apple at the
other end. I would expect that in a very
short time any system which is not really
flexible will be obsolete.
John Stevenson of East Hendred, Oxon.
How long will it be before we can use one
universal/programmable modem that will serve
all the various options for data trans-
mission. 1 am all for flexibility if it can
be achieved at not too great a cost but I am
concerned at the number of promises of
availability or changes in the not far
distant future that come out from many
organisations.
Colin Madge of Croydon.
Yes. 1 think a bulletin board is a natural
and useful extension to the Apple and BASUG
but as an adjunct to not a replacement for a
Prestel/Viewdata system. My own personal
wish is also to have the ability to download
broadcast teletext into the Apple as we!
With speed, 300 Baud is the accepted
standard but 1200 Baud with error correction
is possible. Whilst any decision taken to
ensure a quick service would I think revolve
around 300 Baud and a cheapish modem, 1 hope
this would be only an interim decision to be
extended later if necessary.
Ewen Wannop of Box, Wiltshire.
I have been using both bulletin boards and
Micronet 800 for some time now, the former
with a 300 baud modem andd the latter with
the acoustic modem provided with the
Micronet package for the Beeb. The 300 baud
modem is based on the Maplin kit and runs to
the European standards. The two systems are
really completely different. Micronet and
its parent Prestel are mainly one-way
information sources. It is of course
possible to upload/download programs and
leave messages, but as the system grows it
will rapidly be swamped by the Beeb and
other users. It will then be difficult for
Apple users to find what they want quickly,
unless the BASUG pages are to become fairly
complex. However the 300 baud boards are for
information exchange on a level that is not
swamped by other data. The mailbox
facilities on these boards allow fast and
easy access to information transfer and ease
of directing these messages to anyone as
needed. Program exhange —is_casily
implemented, the limitation simply being the
amount of disk space that can be put
on-line.
Roland Saam of London SW7.
I want to do reliable user to user text
transmission ideally with mailbox facility. 300
baud sounds fine - my volumes of text will
not be large.
Donald MacLean of Chorleywood.
T think:
1, That the Apple presence on Micronet
should be expedited (ie. that the cheap
modem and card should become available pdq),
AND
2. That BASUG should establish a 300 Baud
Bulletin Board, AND.
3, That direct Apple to Apple communication
at 300/300 should be actively fostered.
ene
IMPORTANT
Please read the update.
ereerr ees
Page 30
HARDCORE - The Journal of the British Apple Systems User Group October 1983
Apple compatible Disc Drives
FULL HEIGHT MODEL ADI £167.00
HALFHEIGHT DRIVE 19 Discs FoR
Model LH-1 £167.00 pgives onDeRED
COMING SOON
{ow Cost Printer, A-D/D-A cards
Virtual disk, 128K Rameard
Print Buffer Card, Double Sided Drives
Colour Monitor
Send for Details
Peripheral Cards
for Apple
Disk Controller (runs 13 and 16 sector...
280 (runs all CP/M software).
Printer (Centronics) -
RS 232C oe
Language (incorporating 16k RAM)
Eprom writer
80 Column (not //e)..
PAL card (16 cols on
Games Joystick cea
MEW 52 Key Ascii oded keyboard, Apple
compatible, upper/ lower case
REW Cisp-on Ale cooling fan for Apple IC.
NEw, Sanyo SM12N 12" Green
Monitor s(carr. £7.00)
MEW Star DPSiD Printer, (carr. $7.00)
All cards fully assembled and tested.
MONEY BACK GUARANTEE
Carriage: under £100 add £3; over £100 add £5. Add 15%
to all orders for VAT. Cash, cheques, P.O.’s payable to:
PEANUT COMPUTER
Dewsbury, W. Yorks., WF13 3LX.
Tel: (0924) 499366
TRADE ENQUIRIES WELCOME
October 1983
HARDCORE - The Journal of the British Apple Systems User Group
Page 31
Ceemac
by John Molloy and Colin Holgate
Ceemac is an abstract graphics language
created by an American called Brooke
Boering. It looks a little like Pascal when
written down, and it has two major sections:
the editor and the interpreter. All the
variables are predefined and are prenamed.
Some for example, read the keyboard or give
the state of the paddles or the state of the
cassette input port, others are for tables
and giving random numbers over specific
ranges. It also has a library of almost 30
macros which includes a trace function and
the ability to send sound out through the
speaker.
Mr Boering's concepts are simple to follow
but Ceemac does have some strange
eccentricities. For example instead of
writing a program you compose a score
regarding the graphic displays as visual
scores and not as programs. However if you
also ignore the fact that everything else
connected with the disk has a name (edgar
the editor and cindy the proofreader etc). It
is surprisingly easy to write impressive
abstract graphics.
All the scores from the Fire Organ
demonstration disk are supplied with .the
language in editing form and this gives the
best start to writing your own routines, the
Suggestion being to start with something
which is "sorta close" to what you would
like to see on the screen and then
experiment until you a) get what you want or
b) (the more likely) end up with something
very impressive but not what you were aiming
at in the first place.
When the disk is tirst booted, it comes up
with the Fire Organ logo. Then the program
jumps into the fire-organ routine. In fact
it looks the same as Fire Organ except that
none of the keys apart from the two arrow
controls seem to work. By pressing ctri-A
the screen jumps to text and it is in
editing mode. The current score is the
tire-organ score. To execute it again enter
ctrl-A this is how to move between the
editor and the interpreter. Once in the
editor ctrl-C jumps Ceemac into DOS and to
Tun another score you simply brun it, To
re-enter Ceemac if you jump out accidentally
then just type *800G,
Each score is limited to 256 statements. These
include title, end statement and any
comments. You can only put one statement on
a line. For example one of the scores which
comes with the disk is called ko (Standing
for key O on the Fire Organ disk).
maul
ail
SCORE: KO-21ST CENTURY MAN (SLOW)
: INITIALIZE
SPEED [O30]
CLEAR [0;0]
v2=1
V2 = INCR. FUR Y CORDINATES
2
V3 = INCR. FUR X CORDINATES
7
V4 = SEMMITRY
Page 32
HARDCORE - The Journal of the British Apple Systems User Group
October 1983
MAIN CHAIN
seer uses
INIT. FOR NEW PATTERN
SET COLOR FOR NEW PATTERN
DRAW PATTERN ERASE AFTER 8 LINES
FOR $10
BLINE [CO;V4]
Y2 = Y2 + V2
x2 = x2 + V3
vi = ¥1 + V2
x1 = X1 + VS
BRASE [8303
AGAIN
CEEMAC REL 1.0
From its listings the top line is the title
the colon is the comment symbol. SPEED
{0;0} is the macro which overrides the
paddle setting. CLEAR (0,0) sets the screen
to black. V# are the free variables and can
be set as required. 0 in the line under the
comment : MAIN CHAIN is where the program
loops back to when the left arrow is
pressed. All ceemac programs loop back on
themselves so that when it hits the last
statement (CEEMAC REL 1.0) it jumps back to
the top of the score. SKY {SOF;0} fills the
screen with stars but due to the $OF in the
first parameter it fills the screen with 15
stars. XY2 - RANDOM;$80 is the same as
typing X2 = RANDOM Y2 = $80 and is the end
position for the BLINE macro below, RANDOM
is a random variable between 0-SFF. COLOR=
NXTCOL gets the next colour off of the hires
colour table. COLOR is the variable which
holds the present plotting colour. FOR $10
is the start of a loop which ends at the
AGAIN. It is in hex. BLINE {0;V4} draws a
Straight line XY1 holding the start position
XY2 holding the end and COLOR holding the
colour of the line. The parameter set to V4
in the macro is the symmetry ( if it was set
to O it would draw a single line but V4 is
set to 7 which reflects in all eight sectors
of the screen, Y2 and YI are incremented by
V2 which is set to | while X2 and XI are
incremented by V3 which is set to 2, BRASE
{8;0} erases the BLINE plotted cight
generations later (so after it has plotted
the eighth line it erases the first, after
the ninth the second etc.). After this loop
has been executed sixteen times the computer
jumps to the top of the score.
After a short while | found it quite easy to
understand what was going on and to write
simple but effective graphic displays. Spline
runner was one of my early attempts to write
a Ceemac score, along with it I have
graphics
included some
ul dumps of the
routines.
SCORE: SPLINE RUNNER
AUTHOR JOHN MOLLOY
A CEEMAC SCORE ILLUSTRATING
THE USE OF THE JORDAN CURVE
KNOWN TO CEEMAC AS SPLINES
IF I CAN DO IT ANYONE CAN
SELECT THE FASTEST SPEED
THIS IGNORES THE PADDLES
SPEED [030]
October 1983
HARDCORE - The Journal of the British Apple Systems User Group
Page 33
: NOW CLEAR THE SCREEN BLACK
CLEAR [050]
SET WHITE AS THE COLOUR FOR
PLOTTING
COLOR = $FF
SELECT TO RANDOM START POSITION
BETWEEN 0-127
XY1 = RND7$RND7
XY2 = RND7;RND7
THIS IS WHERE TO LOOP BACK TO
GIVE A RANDOM FIGURE WITH WHICH
TO WEIGHT THE SPLINE
IE THE AMOUNT OF BENDING APPLIED
TO THE SPLINE
XYO = RND73RND7
XYS = RND7}RND7
rere or
: ADD OR SUBTRACT UNTIL THE SPLINE
: HITS A WALL
x1 = X1%2
Vis YL Z%2
: NOW WE GET TO DRAW THE SPLINE
SPLINE (8361
It
I VALUE OF SYMETRY
MAXIMUM FORCE ON SPLINE
ERASE THE 20TH LEVEL SPLINE
PRASE ($1430
LOOP BACK ROUND TO F
EMAC REL 1.0
ee
As you can see it is quite varied even from
@ program as short as this (12 lines if you
take out all the comments. A SPLINE is a
curved line (as opposed to a BLINE which is
@ Straight line) and the mathematical
formula for this macro was supplied by Mik
Jordan (hence the other reference to them as
Jordan's curves) The manual gives a two and
a half page explanation of how they work as
the concept is quite hard to grasp but the
effect is stunning. The graphics dumps don't
give any impression of movement which is how
the scores ‘evolve! in real time.
On the whole Ceemac is an interesting
Braphics package. If you are into fast
moving hi-resolution abstract visuals, then
it is not to be missed. Anything omitted
from the manual is covered in notes left in
BRUN-able files on the disk, and are easy to
access. But if you would just like to see
what Ceemac can do then the package Fire
Organ is for you.
Fire Organ
No amount of describing Ceemac can really
show what it can do for you, as per the
formula 'I picture = 1000 words'. Fortunately
the makers of Ceemac have put together a
‘visual album! of Ceemac 'scores'. This
analogy to music is a good way of putting
things. The ‘Fire Organ' disk (available
from the software library) is a collection
of visual ‘tracks’ created on Ceemac and put
together with another program called
Maestro. By combining many scores together a
variety of effects can be triggered without
having to load in another effect file. This
is done by assigning a separate key for each
score. Altogether there are 34 different
Ceemac files, operated by hitting the keys }
to 9 and A to Y.
In general the different effects are either
moving lines, spline dot lines, kaleidescope
patterns or actual shapes. Many of the
parameters can be altered during these
routines, for example the rate at which the
lines are drawn/erased can be adjusted by
moving paddle 0, or the next lap of the
effect can be triggered by pressing button
0, Also paddle 1 may affect how many lines
appear at once, and button | changes
direction or colour of the lines. This
depends on which of the 34 scores you are
watching. In any case the left arrow
duplicates the role of button 0, and the
right arrow does the same for button 1. By
pressing, hitting or moving these controls
you have dynamic control over the score as
it is being shown. Effectively this means
you ‘play’ the score. This can be very
impressive if the playing is done to music,
at least we hope it's impressive, Mainframe
has used Fire Organ extensively over the
past 10 concerts!
The Ceemac scores on the Fire Organ disk
were written to be accompanied with music.
Apart from the main display program, the
disk also has several binary files on it
labelled ‘About. These are to give the
user an insight into the thinking behind
Page 34
HARDCORE - The Journal of the British Apple Systems User Group
October 1983
Ceemac and the scores themselves. When run
these files display a text account of what
inspired the writing of the different
scores. This seems to vary from a favourite
piece of rock music (Mainframe probably), to
having a drink with a girl friend! Some of
the text is of no particular value, but is
part of a friendly approach that Ceemac has
throughout. This is a bit hard to explain. Put
simply, Ceemac is written in a familiar way,
the sort of program you would write for your
own use. Things are often explained in an
amusing way. We have heard criticism of this
from someone whose sense of humour is on a
different wavelength to Brooke Boering and
Other files explain the different parts of
Ceemac, such as the program editor, the text
editor and other Vagabondo products.
Altogether then, Fire Organ would be worth
buying as a separate product, just to watch
while listening to music. As it is Fire
Organ is effectively free, to help sell the
Ceemac language itself. Ceemac doesn't
appear to be available in Britain, but can
be bought in America. Maestro is also
available from Vagabondo. Further details
are given in the afore mentioned binary
files on Fire Organ.
his friends, but we get on well
friendly method used.
hardcore
Contributions to Hardcore
are always welcomed, Without
them it would not exist.
Whether you have a learned
article, a ‘quick tip’, a
problem or a solution, let
us know.
If you have more than a
short letter, it is helpful
if you could send it on a
disk, with a hard copy it
possible. If you want to
send printed copy, please do
not cut it up but fill
justify on a 9 cm (3,5. ins)
column. We prefer copy on
disk, either as a text file
or an Applewriter I file.
Pascal text tiles and others
such as Wordstar files can
probably be accommodated.
Please use the minimum of
embedded printer commands,
Remember, contributors
receive credits for cheap
Software Library or blank
disks.
with the
APPLE_USERS
/
LOOK WHAT ‘PRACTICAL COMPUTING’
(AUG '83) HAS TO SAY ABOUT THE STROBE:
®.. . . isideal as a tool for a school or college. 9
© It took only a few minutes to get the system up and running. 9
© Unlike a number of other plotters the Strobe is well served
with software. 9
© Agood manual complements the software. J
Produces simple line drawings, graphs, pie and bar charts,
overhead transparencies, etc.
4 Complete system including ‘&PLOT’ disc software and
interface for the Ii and lle.
When ordering please add 15% VAT and £3 for carriage. Pay
by cheque, PO or Access. Send to:
AIMGRAM (09277) 68211
‘Aimgram Ltd, 31 Roman Gardens, Kings Langley, Herts WD4 8LG
October 1983 HARDCORE - The Journal of the British Apple Systems User Group Page 35
DOS EOF
AN ALTERNATIVE DOS END OF FILE
by Richard Teed
One of the problems with reading data files
in BASIC is that it is very difficult to
deal with an end of file, cither data has to
be put in the file to show the end of file
or an "ONERR" command has to be used,
ORG $A626
MSB ON
LST OFF
3
ISBASRUN EQU SA65E
CLSWARM EQU $ae79
CSWSTATE EQU S$AA52
ROTEXT QU SA68C
CLOSFREE EQU SA2FC
RTS5 E£QU SA60D
DOERROR EQU SA6D2
ASAVE EQu $AASC
XSAVE FQU SAASA
IN EQU $0200
DOSXIT EQU SOFB3
5
3 DOS 3.3 READ BYTE ROUTING
i*** READ A BYTE
READBYTE ISR ISBASRUN
BCS CLSWARM
LDA #6
RDB. L STA CSWSTATE
ISR ROTEXT
3
BNE TSTLWR
3*** DEAL WITH END OF FILE
me
OF ISR CLOSFREE
LDA #503
MP CSWSTART
BEQ RTS5S
RD.2 LDA #$05
ame DOERROR
pt** CHECK AND DEAL WITH LOWER CASE
i
TST WR oMP WSEO
acc LL53
AND WS7F
LLS3 STA ASAVE
LOX XSAVE
BEQ LL63
DEX
LDA IN,X
ORA AS8O
STA IN,X
LL63 Ime DOSXIT
Although the "ONERR" command is usable it
has a number of problems the worst of which
is that file reading cannot be done in a
subroutine because the stack is upset.
The following is the DOS readbyte routine
which is used for reading text files trom
disk:-
sls BASIC running ?
f not then shut shop
ySet DOS to state 6 (no output
3 of promot)
sRead a byte from the tile
3 into the accumulator
If not an end of file terminator
sClose the file
Is DOS in state 3 (EXEC)
s1f so then exit to caller
et theerror number fo
n “END OF DATA ERROR"
ils the character lower case ?
s1f not then skip
sElse remove the MSB
sSave A
sGet our position in the input buffe
sIf at the start then skip
sSet the MSB on the character
s(last character planted may have
gbeen fixed for lower case)
3EXIT
Page 36 HARDCORE - The Journal of the British Apple Systems User Group October 1983
As can be seen each byte read is placed in INPUT will be a double CHR$(127). Still,
the input buffer until a null byte is this should not cause any real problems,
returned; then an end of file condition
exists and all text files are closed and an Here, then, is the modified DOS for our
"EN DOF DATAERROR" is output. The exception improved end of file condition (n.b. on end
to this is if the text file is being EXECed, of file you have to do the closing
in which case the file is simply closed. yourself).
What is needed is for a special character to
be returned on the end of file being reached ORG $A626
and for this I have chosen CHRS(127). MSB ON
LST OFF
Ideally a check would be made on the number ;
of characters read into the input buffer. If SKIP EQU $2c
the present one was the first then a RETURN EQU $38p
CHRS(127) ($7F) would be returned. This 1 SBASRUN EQU SAG5E
would satisfy the GET command. If the — CLSWARM EQU 5A679
present character were the second then the CSWSTATE Qu S$AAS2
routine would assume that the command was an RDTEXT EQU SAG8C
INPUT andwould return a <RETURN> character: CLOSFREE EQU SA2FC
thus a CHRS(127) would be returned for both RTSS EQu SA60D
GET and INPUT. DOERROR EQU SA6D2
ASAVE EQU SAASC
Unfortunately things aren't that simple and, XSAVE EQU SAASA
instead of the ottset being zero tor a IN EQU $0200
GET, it's a one, so the <RETURN> character DOSXIT EQu $9FB3
must be returned on the third character (ie ;
when "X" is 2). This will result in the :
single character returned to GET being the
desired CHRS(127) but the string returned to
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