AppleIIIReviewAppleAdsAustralianPersonalComputerFeb1982

bio. Australian Personal. ==. Compute Australia’s leadin micro MaZaZiNe oe | yy 4 LG Jk The Personal Computer Your information window Anextension of your brain An Apple Personal Computer puts you at the forefront of the technological revolution. Use it well and it will mediate the availabilities of a wealth of conceptual tools, data bases, communication channels and information processes. An Apple will help you simplify a myriad of tasks from ordinary data processing through information retrieval toeconomic forecasting. Apple is versatile Your Apple isan ae powerful and robust problem solver backed by a comprehensive set of software programmes. Already, over 300,000 Apples are used for business, domestic, educational research and recreational purposes. Apple as information processor An Apple personal computer performs a full range of standard functions like statistics, word-processing, graphics, number crunching, filing, storage/retrieval and cross-referencing. Apple is cost-efficient For roughly the price of a plain paper copier, you get a sophisticated, powerful machine, which not only processes numbers and words, but gives you direct access to a wealth of inform ‘ ation through a rich network of data bases and direct communi- cations with other computers Mail this coupon for an “Apple Pack” brochure or talk to your local Apple authorised dealer about the specific applications for you. Ifthe coupon has been removed, send your name and address to ELECTRONIC CONCEPTS PTY LTD, 55-57 WENTWORTH AVENUE, SYDNEY, NSW 2000. apple computer Apple assuper-brain Aside from the more pedestrian functions of retrieving and processing information, Apple performs other sophisticated functions such as econometric modelling, financial forecasting, graphics, topological modelling and trend analysis. Apple is convenient Apple is portable. It can be used at homeor in the office. You can address it in ordinary English or gain full computer literacy in BASIC PASCAL, COBOL, FORTRAN or PILOT. Full step-by-step training comes with your Apple. If youcan use a calculator and speak English, Apple shows you the rest. Apple as communicator Apple combines many of the functions of telephones, telexes, citizens’ band radios and library access terminals. It allows you the very latest access todata bases and information services and mail electronically locally or world wide. Apple aschallenger Apple is fun. From a perfect game of Chess to Star Wars—not only for the children— preparing them for the future in this high- technology age. Mail to: PPCB374B ELECTRONIC CONCEPTS PTY LTD, 55-57 WENTWORTH AVENUE, SYDNEY, NSW 2000. Please send me a free “Apple Pack” brochure SANS Stee ADDRESS é POSTCODE ——— PROFESSION — Aa ae Sse “APPLE. APPLE= PERSONAL COMPUTER. PERSONAL COMPUTER: APPLE APA RiXTOvT Computer and course cost $295 including freight. Computer Galerie is at 66 Walker Street, North Sydney, NSW 2060; Tel (02) 929 5497 MASTER PLANNER Informative Systems has a new Cromemco financial plannin eneral purpose numeric analysis packag called Planmaster. It provides automatic spread- sheet analysis for financial planning cost accounting, sales forecasting, production planning, cash flow analysis, scientific data evaluation, and hundreds of other applications. Data entry is via direct cursor positioning to the desired location, with decimal positioning done automatically A plan can include up to 1010 lines or up to 130 columns, limited by a maximum of 12,000 entries. Each line or column can be given a user-defined label, while mathematical relation: ships between the entries may be defined in terms of these labels. Available on S inch or 8 inch diskette for $395, from Informative Systems, 337 Moray Street, South Melbourne, Vic 3205; Tel (03) 690 2899 increases the storage capacity to almost 10 million bytes, with the 8 inch floppy diskette back-up providing an additional 1 million. The floppy is provided for back-up, data interchange and portability of programs and data, It is compatible with the industry standard IBM 3740 format and will record in single or double density ; either single sided or double sided. The diskettes are also compatible with the Z-A7 dual 8 inch system, which has been around for a year The floppy disk drive sits alongside the Winchester in aca A switching supply is built in. The new drive connects directly to the back of the Z-89 or Z-90 micros using a flat cable. pinet power LEARN WITH ZEST Zenith Education Systems will running two nning in courses March. omputer and Computin Getting Started” it is for complete novices; and “Basic Programming” will include graphics and sound generation. There will be practical work and class sizes will be restricted to one instructor for five students. early For further details, write to Zenith Education Systems, P.O. Box 505, Bankstown, NSW 2200; or ring (02) 708 3140. WINCHESTER, More from Warburton Franki for the Zenith micros. An 8 inch Winchester disk drive with floppy disk back up has been introduced by Zenith Data Systems for its business machines. The non-removable Winchester in the new Z-67 PS. The latest rumours about Hitachi are incorrect. Contrary to the opinions in the APC art room, no left hand versions of the Peach are beit manufactured, For one: source is both authc and emphatic (!) The Zenith Data Systems Winchester disk drive. ge Sa Co ee ce ges en Bk eee SAVE! SAVE! applic 3 BUILD AN FEATURES: * runs Apple software * will take all add on cards as it has same type BUSS * PAL is on main board, saves buying a PAL add on card * board is fully socketed and has all passive components and crystal. Just add IC’s, ROM’s, keyboard, power supply and case. * plug straight into your home colour TV via RF modulator and save on buying a monitor. Dealer enquiries invited abacus 512 Bridge Road, Richmond, Vic. 3121 Telephone (03) 429 5844 TM Reg trade mark of Apple Computers Inc: AVAILABLE FROM: RITRONICS WHOLESALE COMP-SOFT (03) 481 1923 (03) 428 5269 MICRO-BASE (WA) (09) 328 9308 MICRO VISIONS (NSW) (02) 662 4063 CUSTOM COMPUTER SERV (QLD) (07) 204 4995 COASTAL COMPUTERS (TAS) (004) 31 3259 ee APC 11 APPLE III The Apple III first appeared as an ever changing set of rumours in 1979, when people realised that Apple’s considerable development effort was about to produce a new machine. The machine was released at NCC 81 and quickly gained a reputation for being bug-ridden. Consequently, the machine was put on hold while the problems were fixed. Most of them were associated with chips coming loose from the sockets in the motherboard and clock chip stability. The release of Pascal IIIf and the Profile hard disk system provided Apple with an opportunity to relaunch the III and to express their satisfaction with the product. Steve Jobs has said that Apple intends to build a range of machines exploring the dimensions of the personal computer, and this has been the basis of Apple’s design philosophy. These machines are based on large RAM based computers supported by soph- isticated operating environments. This evaluation was written during a Festival of Sydney workshop. People with experience in video, audio and photo- graphy were being introduced to com- puters as a creative medium. The experience of the workshop really confirmed the importance of Steve Jobs observations. THE STANDARD MACHINE The Apple III is a 6502B based machine with 128k of RAM memory. There is a built-in 5.25 inch floppy disk drive. The machine has an RS232B port, two joystick interfaces, video and audio ports, a Silenttype printer interface and four expansion slots. The system is packaged with a separate monitor: either colour or green screen. The SOS operating system, Business Basic and Visicalc are supplied with the machine. The expansion options are to daisy chain up to three floppy disk drives from the built in drive, the Profile hard disk and Apple Pascal III. HARDWARE The Apple III has a cast aluminium case with an extended keyboard. The motherboard is under the case. There is a moulded plastic cover over the built-in disk drive, the power supply and a space for four expansion boards. The computer is fairly heavy and sits firmly on the table. The keyboard extends from the front of the computer, and could easily have been detachable. The key- board has 61 keys and a 13 key keypad. All 128 ASCII characters can be generated and all keys have auto-repeat. (The four cursor keys have two speed auto-repeat.) The keyboard is an improvement on the Apple II keyboard, but the keys still feel a little insecure. A 5% inch (140k) floppy disk drive is built into the lefthand side of the case. The disk controller is on the motherboard and can accommodate three daisy chained drives. A 2 inch speaker driven by a six bit DAC is mounted in the center of the case. The motherboard is a 15 inch x 10 inch board that is only accessible from the bottom of the case. The board con- tains all chips except for the RAM which is contained on a piggyback card that has 32 16k bit RAMs and 16 32k bit RAMs. The board can take 256k RAM. There is only 4k ROM on board and a number of unidentified proprietory chips. An empty socket is intended for the clock chip, and an empty space for the clock battery. The board is well designed with only one wire jump and has a number of undocumented plugs that may provide access to features of the system. All interface connectors are on the back end of the motherboard. The expansion sockets are accessed through the top of the computer. Video signals available on the board are PAL B&W, PAL composite video and true RGB video. A variety of text and graphic display modes are available. The standard text display is 80x24 characters, with options for 40x24 black and white and 40x24 with 16 foreground and background colours. Graphics modes are 280x192 and 560x192 in B & W. Color modes are 280x192 with 16 colours and a com- posite 140x192. Colour is displayed as a grey scale on a B & W monitor. The board has several memory management switches to support a 64k RAM space with the 6502 processor. The boot ROM is mapped into $F000- SFFFF and is switched out of memory space after system boot. The memory mapped I/O space at $C000-$CFFF can also be switched out of address space and replaced with RAM and system supports multiple stacks. The Environment register at SFDFF, used to reflect the state of the system, is a good example of the type of hardware environments that can be established. ENVIRONMENT REGISTER BIT ‘USE CLEAR SET 7 Clock Speed 2Mhz 1 Mhz 6 $C000switth RAM ROM 5 Videooutput Off On 4 RESET key disable enable 3 Protect$CO00 On Off 2 Stack reloc $100 1 $FO000 switch © ROMA ROMB 0 $F000 RAM ROM The hardware is an innovative design to provide an environment that will support more than 64k of memory and integrate standard peripheral devices into the motherboard. The Apple III was designed to provide a standard set of peripheral devices on the motherboard and to support a hard disk. Apple began to develop a hard disk system for the Apple III in 1980, based on a Seagate 5Mb drive, and the PROFILE hard disk system has just been released. The disk is enclosed in a small moulded plastic case (15” x 8” x 4”) in regulation Apple colours. Install- ation of the disk requires that a driver PROFILE be configured into the system and the interface card plugged into the Apple III expansion slot so that the disk is then fully supported by the SOS. A good feature is the quietness of the drive, even during extensive disk search- ing. There is a parallel card tor the Apple III and other cards are being developed. Overall, the expansion bus is very similar to the Apple II bus: small inter- face cards that do not use a lot of the bus will work in the Apple III system. Microsoft is developing a Z-80 Softcard. The Keyboard Company has developed a joystick and M&R Enterprises have released a RGB video interface box. SOFTWARE The system software for the Apple III consists of 4k boot ROM and the SOS operating system. The motherboard ROM contains the system boot code and a series of diagnostic tests that are performed after every boot. The diagnostics test RAM, ROM, I/O ports and the memory management hardware. The. ROM also contains an undocumented monitor with similar functions to the Apple II REVIEWED by Ian Webster. monitor. Memory can be moved, verified, displayed and searched. The monitor can also Read and Write disk blocks. SOS provides a complete environ- ment for all software on the Apple Ill. The system has combined the Apple DOS user command interface with the structure of the UCSD operating system and UNIX style hierarchical directories. A uniform interface to the system is provided for all language implemented on the Apple III. SOS provides extensive high and low level calls to the system. It consists of KERNEL, which has the low level interface to the system hardware, a DRIVER file that contains the interfaces that all peripheral devices configured into the system, and a P-code interpreter. SOS has five component interfaces. The first is the file management inter- face. All devices in the system can be treated as clock or character structured files. A hierarchical directory structure is used where each device has a root directory that may contain both files and other directories. The location of a file is specified by the pathname of the file. The root directory must be specified followed by the other direct- ories until the directory that contains the file is reached. A file called DEMO.CODE that is in a directory called MYDISK on the Profile hard disk would be accessed by the pathname :— PROFILE/MYDISK/ DEMO.CODE. This feature is one of the hardest for Apple II users to get used to, but provides a powerful facility for the management of files on large orage devices. fe A Teese is that SOS, in its provision of a universal interface for all languages, has a proliferation of file- types. It supports 13 filetypes, from SYSTEM to UNKNWN. The second interface is the device management interface that provides access to the drivers. The drivers accept control codes for the operation of the device or to report on status enquiries. The CONSOLE driver controls cursor position, screen window size and text colour. The i28 byte type ahead buffer and the software definable character sets are also controlled by the CONSOLE driver. The keyboard can also be remapped through the device control interface. The GRAPHIX driver provides control over the colour options table and the type of point plot on the screen. The RS232B interface can specify baud rate, data format, buffer size and a choice of no, XON/XOFF or ENQ/ACK communication protocols. The third interface is the memory management interface that manages the allocation of memory in the system. Switches control the bank select, I/O space select and the ROM select. Memory management also controls stack relocation and the management of memory in the system. Interrupt management is largely handled by SOS, although a_ user interrupt mechanism has been imple- 14 APC 128k Apple MK enn $C000 System CAN BE Space 1/0 Space TECHNICAL Lie cated i 5” x I PROFILE HARD DISK Disk Surfaces 4 Heads 4 Tracks/Surf 153 Sectors/Trk 16 Bytes/Sector $32 Rotation 3600 RPM Seek time 95 msec Data trans 5 Megabits/sec Size 8.2” x 4.8” Cast aluminium base with plastic moulded cover Weight 26ibs Processor 6502B with extended addressing hardware Clock Speed 2Mhz peak, 1.4Mhz average RAM memory 128k ROMmemory 4k Disk Storage One 5.25 inch floppy disk (140k) Keyboard 74 Keys with auto-repeat, generating the full ASCII set Screen Text 40 x 24 Black & White 80 x 24 Black & White 40 x 24 16 foreground and background colours All characters are software definable Graphic 280 x 192 Black & White 280 x 192 16 foreground and background colours 140 x 192 16 colours 560 x 192 Black & White Video Output Black & White Composite colour RGB pure video Signals Pal standard Audio output 2 inch speaker with a 6 bit DAC Serial 1/0 RS232B port Joystick 2 joystick interfaces Printer Apple silenttype interface Expansion 4 50 pin expansion slots Seagate drive — 5M formatted data mented that preserves the priority of SOS peripheral interrupts. The utility interface provides access to the software clock and joystick ports in the system. The SOS software includes a utilities disk that is an enhanced version of the Pascal Filer. The system support soft- ware is written in Pascal. This utility allows manipulation of disks and files, format disks and generation of a new system. Apple III Pascal is an enhanced version of Apple UCSD Pascal 2.1. SOS has lessened the severity of the UCSD operating environment. Several additions have been made to the system including an OTHERWISE clause for the CASE statement, Bytestream and Wordstream datatypes, conditional com- pilation and the implementation of the IEEE single precision floating point standard. The general parameters of the system have been enlarged to utilise the available memory space. A compiler option ($SETC APPL! ) generate code that is compatible with Apple II Pascal. Essentially, the Basic has been written to the Microsoft V5.0 standard with several extensions. The language has adopted the Microsoft format for Disk instruction (OPEN #1 AS OUTOUT). The most interesting feature of the language is the implementation of LONG INTEGERS with 19 digits for financial programming, a powerful PRINT USING statement, indented program listings to highlight structures, and ON KBD and ON EOF# _ sstate- ments, There are no PEEK, POKE and CALL commands. The _ interface between Basic and machine code is contained in the INVOKE and PERFORM commands. INVOKE will load a machine code file into memory. SOS handles all memory management details and decides where to put the file. PERFORM will call the routine passing a parameter list via the stack. PEEK and POKE have no place in an environment where the system is capable of managing the environment and where there is enough control with system calls to interrogate the system. If PEEK and POKE functions are required then a machine code routine can be written to provide the information. A separate graphics module provides commands to Draw images, points and lines and to Fill screen area and control colour selection. Business Basic should have been available for the Apple II years ago, and will make Apple II programmers realise the inadequacy of the Apple- soft Basic implementation for serious programming. Apple has released an enhanced version of VISICALC for the III and has a word processor called Word Painter almost ready for release. Several Special Delivery Software packages have been released, including Apple Writer. There are at least six other word processing programs available for the Apple III. Enhanced versions of Desktop Plan and PFS are also available. The PFS dealer disk includes an impressive demo for the Profile that contains all of the Skarbeks current software directory. Paul Lutus has also produced versions of his assembler, ALD III and Forth, TransForth III for the machine. The manuals are a delight to use, explaining the operation of the system in clear and patient style. The documentation assumes that the user is reasonably computer literate and there is little tutorial material. The specifi- cation of Business Basic and Pascal is excellent, but I get the impression that Apple has omitted a lot of technical information in an attempt to dissuade people from tampering with SOS. The manuals have been written from the programmers point of view and provide all the information necessary to use the system. APPLE Il EMULATION The Apple Il emulation mode con- verts the Apple III into an Apple II. faa —_appi¢ Your Key to the Future THE COMPLETE APPLE COMPUTER 48K Apple ][, GREENSCREEN MONITOR DISK DRIVE AND EPSON MX 80 PRINTER APPLE ]I[NOW AVAILABLE WORD PROCESSING: $295 EXTRA ACCOUNTING AND BUSINESS SYSTEMS A MOEBIUS COMPUTER COMPANY 96a Pacific Highway, ROSEVILLE, 2069 (Opposite the Station) IPhone: (02) 46 6521 Open 7 Days. Phone Inquiries Welcome Authorised Agent for: The clock speed reverts to 1 Mhz and memory is configured to a 48k Apple. The emulation disk can provide Integer or Applesoft in ROM and the Apple III serial port can be configured to emulate an Apple high speed serial card or a communications card. The con- figuration cannot be changed without a reboot of the emulation disk. A wide variety of Apple ‘I programs were tested under emulation mode including several games which are known to exploit features of the Apple II. All programs executed without any problems. Problems could occur with the game socket because the Apple III emulates the paddles using joystick ports. If a program does not use a standard paddle driver then the Apple III joystick may not respond correctly Not all of the features of the Apple III keyboard can be used in emulation mode as the keyboard is remapped and A.H. 411 716 some keys do not generate ASCII codes that correspond to that key. CONCLUSION The power of the system is not in the hardware but in the complete machine environment . The major achievement of the system is compatability with Apple II while building a software system that provides independence from the hardware design of future Apple computer systems. The machine will be a delight for programmers, perhaps a little daunting to the home hacker and a powerful work station for users who require a computer system to assist with their work. Anyone with an information management application that requires a small hard disk should consider the Apple IIL. oe APC 15 City Personal Computers FEATURES THE S 75 CASTLEREAGH ST SYDNEY 233 8992 233 7591 appie_ The APPLE II is Australia’s most popular and versatile computer. Nowhere will you find it better supported than at City Personal Computers. We have all the Software and accessories for business and pleasure, to ensure that your Apple system is a success from day 1. And the experi- ence of our Apple-trained staff will keep you one step ahead Apple FAMILY SYSTEM Apple's Family System com- bines hardware, software and manuals into a highly market able package geared for the first time computer user $2780 om, ahs The Apple Ill is a powerful desktop computer htat will solve complex problems and increase personal productiv ity. If you are a manager, en: gineer," financial analyst, accountant, or other profes- sional - and you're looking for an affordable answer to your computer needs - you owe it to yourself to view this machine. Price on application. 16 APC @HITACHI “PEACH At $1495.00 the Peach in cludes the following features Industries highest density graphics (640x200), 8 num eric key pad programmable function keys, built-in RS 232c serial and __ parallel interfaces, six expansion slots, 32K RAM, 24K ROM, RAM expandable to 64K in microsoft basic, machine language. TARS Fok 82 ‘ Epson N C commodore The VIC 20, a small but pow: erful colour machine, takes us another big step closer to the ‘every home should have one’ ideal of personal computing. This is our lowest priced colour computer system Demand far exceeds supply so check first on availability $399. City Personal Computers C.P.C. has established itself as Sydney’s lead ing supplier of Microcomputers for business or home use. We stock the most popular systems, together with a complete range of accessories and the widest selection of software in Australia. We have everything from disk drives and printers to full business packages, education systems and game programs. So whatever your computer needs — from business forecasting and analysis, to games and education — rely on us for the best Micro computing. $1445 Is a printer that must be seen to be believed, It features un- matched correspondence qual -ity printing, and an ultra- high resolution bit image graphics capability. Then the ability to print up to 233 columns of infor- mation on 15’ wide paper to give you the most incred- ible spread sheets you're ever likely to see Deal with Australia’s largest - EPSOM dealer. Why? Call. Epson F/T Type II $1145 This has all the same print- ing facilities as the MX 100 in a smaller package. Olympia Whisperdisc This is the best value and best performing typewriter/printer available giving superb quality print at a reasonable price. It even has its own built-in com- munication capability. So check with us for the full story $1995. WORD DEC ADDR (HEX) woRD DEC ADDR HEX) HOLD 62 3E FEPAIR 100 64 HOT 63 SF REPEAT 101 65 IN 64 40 FEPLACE 102 66 INCORRECT 65 41 ROOM 103 67 INTRUDER 66 42 SAFE 104 68 KEY 67 43 SEZOND 105 69 LEVEL 68 as SEZURE 106 6A LIGHT 69 45 SELECT 107 6B LOAD 70 46 ¢END 108 6c LOCK 71 a7 SEPVICE 109 6D LONGER 72 48 SIDE 110 6E MORE 73 4g SLOW 111 6F MOVE 74 aA SLOWER 112 70 NEXT 73 48 SMOKE 113 71 NO 76 4c SOUTH 114 72 NORMAL 77 4D STATION 115 73 NORTH 78 4E SWITCH 116 74 NOT 79 4F SYSTER t1% 75 NOTICE 80 So TEMPERATURE 118 76 OPEN 81 Si TEST 119 77 OPEPATOR 82 52 *T™* 120 78 OR 83 53 THANK 121 79 Pass 84 =4 THIRD 122 7A PER 8s ss THIS 123 7B POWER 86 56 TURN 124 7c PRESS 87 7 UNDER 125 7D PRESSURE 88 58 USE 126 7E PROCESS 89 59 WAITING 127 7¢ PULL 90 SA WARNING 128 80 PUSH 91 SB was 129 81 PUT 92 sc WATER 130 82 QUARTER 93 SD EST 131 83 RANGE 94 SE WIND 132 84 REACHED 95 SF WINDOW 133 8s RECEIVE 96 60 YELLOW 134 86 RECORD 97 61 135 87 REVERSE 98 62 ZcNE 136 88 RED 39 63 QUEENSLAND’S FASTEST GROWING APPLE DEALER 600 OLD CLEVELAND ROAD, CAMP HILL, 4152, BRISBANE. Sole Queensland Distributor THE AUSTRALIAN SOURCE CITY Introducing ‘THE CASIO’ FX-9000P The Engineers’ Computer Calculator. THE ‘NEC’ PC 8000 DESK TOP COMPUTER. See us for our ever growing range of Hardware. Phone Horrie or Richard now for details 398 6759, 398 6571 APC 31 Now, having added the ABS function into line 30 to ensure that IV_ will always be positive, I am not sure that I have gained anything in efficiency. But, I think that it is more elegant, so I'll leave it! If you try to run the program the way it is, you may have a problem: if the item that you are searching for is not on the list, you will get into an infinite loop and the only way out of the algorithm is to find the item. So, we have to check to see if IV has the value of 1. If it does we cannot cut in half any more; we cannot search any more. We need to test IV’s absolute value, and I put it right after the com- pare, calling it line 25. 25 IF ABS(IV)=1 (the search has failed) If everything in the world were perfect, that would be the algorithm. However, since consistently rounding IV up for the reasons pointed out above, we may actually, at some times, exceed the bounds of the array, raising the error condition. There are several different ways to handle the problem; I believe the easiest is to take the value of IV away from PT and continue on from there. Since I don’t know at this point if IV is negative or positive, I simply change its sign and add it to PT in line 55. 55 IF PT>TL OR PT>1 THEN IV =-IV:PT=PT + IV (if you really don’t like to have IV go negative and then to have to use ABS, you can use the original version of lines 40 and 50, and then use two state- ments here in place of 55. IF PT<1 THEN PT=PT + 1V and IF PT > TL THEN PT=PT-IV) My version of the binary sort algorithm is shown in figure 2. THEN GOTO 10 PT=INT(TL/2+.5): IV=PT 20 IF L1$(PT)=SW$ THEN GOTO [found it! PT is the number of the item] 25 IF ABS (IV)=1 THEN GOTO [the search has apparently failed] 30 IV=(INT((ABS(IV))/2+.5) 40 IF L1$(PT)>SW$ THEN IV=-IV 50 PT=PT+IV 55 IF PTTL OR PT<1 THEN IV=-IV: PT=PT+IV 60 GOTO 20 Figure 2 There is, unfortunately, still one more potential problem. If the number of items in the array (TL) is exactly a power of 2 (16, 32, 64, 128, etc), the search will not locate the very last item in the array. The reason is that when you cut in half, you don’t cut perfectly in half. If the array has 16 elements in it, you look first at element 8: there are actually 7 elements above it in the array; but there are 8 elements below it! If the array has any number other than a power of 2, there is always one division which has to be rounded up, and that rounding up gives us room to get to the very end of the array. (Actually, it also caused the problem of going’ beyond the bounds of the array, which made us add line 55.) There are several ways to overcome the problem, including preventing the array ever from having an “undesirable” number of items. For me, the simplest thing to do is to check the last item in that array if the search fails. If they don’t match, then the search actually has failed. But if it does succeed at this point, I do have to assign the value of TL to PT, as PT is what is carried into the main program to tell what item number was found. I do the entire thing in line 70: 70 IF SW$=L1(TL) THEN PT=TL:GOTO [found it] I also have to change line 25, so that the GOTO there branches to 70. If the compare in line 70 yields a false, then the search has really failed, and you drop out of the binary search algorithm. Let’s now look at the com- plete algorithm in figure 3, which is missing only the line numbers after the GOTO statements which will link the search to the programs you use it in. 10 PT=INT (TL/2+.5): IV=PT 20 IF L1$(PT)=SW$ THEN GOTO [found it] 25 IF ABS (IV)=1 THEN GOTO 70 30 IV=INT ((ABS(IV))/2+.5) 40 IF L1$(PT)>Sw§ THEN IV=-IV 50 PT=PT+IV 55 IFPT TLORPT 1 THEN IV=-IV: PT=PT+IV 60 GOTO 20 70 IF SW$=L1$(TL) (found it] THEN PT=TL: GOTO 80 REM Search has failed and you're out of the binary search algorithm, Figure 3 computers. ATARI 800 & ATARI 400 LOWER GROUND FLOOR, ™““©@®SYDNEY STORE, GEORGE & MARKET STREETS, SYDNEY BOX 672, G.P.O., SYDNEY, 2000, TELEPHONE (02) 238-9984 Invite you to come and leisurely compare our 20 Computers, various Disc Drives, several Printers, and a large selection of software for all our COMPUTERWAVE has the largest stock of ATARI 400 & ATARI 800 Computers in Australia, together with a wide selection of ATARI and Independent Supplier’s Software. COMPUTERWAVE also stock APPLE COMPUTERS & SOFTWARE COMPUTERWAVE are able to give expert & friendly advice to the First Timer or the Experienced User ASK FOR OUR PRICE LIST ANC CATALOGUE We carry a large stock of ATARI 400/800 Computers Discs — Selection of Printers — Atari Visicales — Space Invaders — Scram Tanks — Mailing — Word Processing and a large selection of Business, Personal, Educational and Entertainment Programs. We accept Bankcard, American Express, or use a Myer Account MAIL ORDERS INVITED 44 APC JHCAL 7C4F 07410 JAP 7C46 07349 03740 KEYED 3801 00280 KEYEXP 7D64 01040 KLOOP 7DFE 00570 ypprsasgeaenae: ha gaeese"a TRF? 03060 STRING 7DBA 01320 TABLE, 7ESB 03270 0 NINDUP TDD 02810 WORDLP 786 02240 5340 073 Seri= SWAP 666 GYMPIE ROAD, LAWNTON. Q’LD. 4501. A joining fee of $15.00 per year allows you to exchange programs (originals NOT copies). For details about SOFT — SWAP send $15.00 to become a member, or a stamped self addressed envelope to: SOFT — SWAP, P.O. Box 22, Zillmere. Q’ld. 4034. Name Address wou. SOFTWARE FOR APPLE IT. WELCOME. AVANT GARDE WE DEAL ONLY IN QUALITY PROVEN SOFTWARE CREATIONS HI-RES SECRETS INCLUDES © Vector Shapes Sound (Machine Language) @ Block Shapes for Applesoft or assembly @ Animation (Machine Language) © Page-Flipping © Font Programs @ Hi-Res Scrolling © Music (Write: Record: Play) @ Hi-Res Colour Palette H PLOT SHAPES A graphics package like no other in existence. Now you can design programs that will easily and automatically create dozens of multi-coloured scenes and/or shapes .. . All necessary instructions and machine language routines included. $1490.95 ULTRA PLOT — No plotting utility can match ULTRA PLOT for flexibility, ease of use and uniqueness. Full stats, incl mean standard deviation, slope, Y intercept, coefficient of correction and more. Pie charts, scatter charts, line charts and map charts. $79.95 HI-RES COMPUTER GOLF HI-RES COMPUTER GOLF features the following: @ Five 18-hole courses from Beginner to Championship @A golf bag full of golf clubs to choose from @1 to 4 players @ Amazing Dynamic Club-Swing Control @Wind Gauge @ Multi-screen Fairways @ Contoured greens to make putting a challenge @ Fairway Obstacles: sand traps, roughs, water, trees, high winds, boundaries @ Computerized Scorecard and display options to aid your playing @Mach. Lang. Sounds and Full Hi-Res Colour @ No Green Fees @ No Waiting @ Yelling “FOUR” is optional. $39.95 Senith» Eaducation Systems P.O. BOX 505, BANKSTOWN, NSW. 2200. OR SEE YOUR LOCAL APPLE DEALER. 72 APC Gepric See the Apple If Computer at The Logic Shop. The Logic Shop has a full range of Apple hardware and software including Visicalc, games and business systems written in Australia for small businesses, insurance brokers, farmers and doctors. We also have systems especially designed for schools and home education. When you add The Logic Shop’s professional level of customer support and service we offer a very attractive Apple Deal. Call us today and see the amazing Apple II demonstration. Computer Systems. 212 High Stre 91 Regent Str , Prahran VIC 3181. (03) 51 1950, 529 2771 t, Chippendale NSW 2008. (02) 699 4910, 699 4919. Shop 16 Civic Arcade, Adelaide Street, Brisbane QLD 4000. (07) 31 2330. HOBART OPENING SOON! Bankcard Welcome LSI-024 GLOBAL SOFTWARE NETWORK UTILITIES: GRAPHICS 1 Resolution of 128x90. Fantastic demon: stration includes screen motion, X-Y-Z. plotting, bar charts, circles and stars. Figures can occupy the entire screen if desired. $25.95. GRAPHICS 2 Resolution of 512x240 using X and co-or dinates, It is persimonious, May beac essed from other BASIC’s besides Exidy’s Rom-Pac Basic. A dedicated interface is provided for the convenience of Rom-Pac users, Includes superb demonstration $25.95, Both Graphics 1 and 2 include point and line drawing features in machine code. SUPER DISASSEMBLER This is a very fast two pass disassembier written in machine code. It produces a 2-80 assembly language source file with labels that is directly compatable with the Sourcerer Development Pac. The disassembler has a Displacement func tion which allows any program residing anywhere in memory to be decoded, whether it is at its normal address or it has been moved to be decoded The output can be set to video, printer or cassette, The cassette file can be read into The Editor or Assembler of the Develop: ment Pac 92 APC These programs and more available from Customized Technology, P.O. Box 461, Ashfield. NSW. 2131. Phone ( Also available from: City Personal Computers; Electronic Agencies and other outlets. Ask for free catalogue. Several versions on tape at different mem ory locations.(N.8. Development Pac not necessary). $21.95. EZYFILE A general purpose database system for handling alphanumeric data. Written in Z 80 machine language and useful for cata jogue/filing data, mailing lists, music {i braries, club membership etc. etc. Files may be stored on disk under the CP/M 1.4 or later operating systems. Commands available: Create, Load, Merse, Save, Add, Delete, Edit, Sort, List, Report, Total, Printer, and more. Cassette $35.95. Vista FDS etc. floppies $39.95 4 VOICE MUSIC SYSTEM The software enables you to easily write music as it displays both the treble and bass staffs on which one moves the cursor up and down to place the desired notes for each four-part chord. Features clude © hearing @ hearing a note before it is selected @ transposing @ copying refrains @ tempo contro! 6 full editing to insert and delete notes in the music file @ key signature selection @ graphical notes and musical symbols. Includes music files, hardware h connects to your stereo and throughout documentation The music generation machine easily inter faces with your programs. $54.95 (Compare this with 1 Voice S-100 cards costing over $300!!) SORCERER SOFTWARE GAMES: PUNT Graphical and musical horse race with sound effects. $11.95 HEAD-ON COLLISION You must avoid the computer controlled car. Three levels of play, $16.95. BASEBALL You play against the computer in this highly graphical game. $15.95 MILITARY ENCOUNTER A graphical war game played on a board This could also be called Encounters of The Final Kind! $15.95. ARCADE GAMES WITH SOUND: CHOMP THE GHOST MUNCHER This is the Sorcerer's high resolution version of the classic real time arcade game. $21.95. MISSILE DEFENCE You command your countries defence centre to protect against a foreign attack. As the missiles drop, you must fire at them while attempting to protect your cities and missile bases. $19.95 CIRCUS An arcade game in which you must keep the performers bouncing on a trampoline and bursting ballons above. $19.95 799 6373 " i | NTT SOLt ware trom icro- E ti I | ducationa | APPLE SOFTWARE APPLE PERIPHERALS FROM MICRO—EDUCATIONAL Australia’s leading mail-order supplier for Apple Software and Peripherals. We offer wide range, phone | advice, fast delivery ex stock, 10-day money-back warranty on Software and very competitive pricing. HARDWARE (Prices exclude sales tax BAITLE OF SHILOH 64.95 FIREBIRD 32.95 Add 17.5% S.T. if applicable.) CONFLICT 27.50 DAVID'S MIDNIGHT MAGIC 37.50 SOUTHERN COMMAND 43.95 RED ALERT 29.95 ANDROMEDA 16K EXPANSION OLYMPIC DECATHLON 29.95 SHADOW HAWK 34.95 CARD 195.00 GLOBAL WAR 29.95 BEER RUN 29.95 MICROSOFT Z80SOFTCARD —-379.50 HIRES O (MISSION ASTEROID) 23.95 RINGS OF SATURN 43.95 PAL COLOUR CARD 195.00 HIRES 1 (MYSTERY HOUSE) 2750 ESCAPE FROM ARCTURUS 39.95 CCS ASYNCH SERIAL CARD 185.00 HIRES 2 (WIZARD & PRINCESS) 37.50 SHUFFLEBOARD 32.95 GCS COMMUNICATIONS CARD 210.00 HIRES 3 (CRANSTON MANOR) 41.95. GAMMA GOBLING 32.95 CCS PARALLEL CARD 159.50 HIRES 4 (ULYSSES) 39.95 PEGASUS II 32.95 ccs A/D 145.50 HIRES 5 (TIME ZONE) 109.95 HADRON 32.95 CCS CLOCK/CALENDAR 149.50 SOFTPORN ADVENTURE 32.95 THIEF 32.95 CCS COMMUNICATIONS CARD 185.00 ULTIMA 43.95 CCS GPIB IEEE 488 320.00 ZORK 37.50 THRESHOLD 43.95 CCS ARITHMETIC PROCESSOR 495.00 ZORK I 37.50 CROSSFIRE 32.95 MH CPS MULTIFUNCTION CARD 275.00 00 TOPOS 3750 MAZEMAN 32.95 WESTSIDE SUPERCLOCK 195.00 CYBORG 37.50 ELECTROMED SENDATA GALACTIC EMPIRE 29.95 GRAPHICS COUPLER 325.00 GALACTIC TRADER 29.95 PAYMAR LOWER CASE 49.95 GALACTIC REVOLUTION 29.95 BUDGE GRAPHICS 43.95 16K RAM UPGRADE 49.95 TAWALA'S LAST REDOUBT 32.95 SUBLOGIC 3D GRAPHICS 69.95, BLANK DISKS (10 IN LIBRARY CRUSH CRUMBLE CHOMP 32.95 2-301 ENHANCEMENTS 29.95 45.95 TEMPLE OF APSHAI 29.95 A2-3D2 GRAPHICS EDITOR 39.95 LIBRARY BOX 4.50 AKALABETH 39.95 APPLE WORLD 69.95 T&G PADDLES 44.95 STAR WARRIOR 42.95 HIGHER TEXT 39.95 JOYSTICK 69.95 ROBOT WAR 39.95 HIGHER GRAPHICS II 39.95 ABT BARCODE READER 199.50 CASTLE WOLFENSTEIN 32.95 COMPLETE GRAPHICS SYSTEM 69.95 DUNGEON CAMPAIGN/ DATASOFT MICROPAINTER 39.95 SOFTWARE (Tax included. Sales Tax WILDERNESS 34.95 EZ DRAW 3.3 57.50 exemption does not apply.) ORAGON'S EYE 24.95 PASCAL GRAPHICS EDITOR 109.95 DARK FOREST 32.95 ARCADE MACHINE 49.95 ADMINISTRATION STONE OF SISYPHUS 32.95 UTILITIES & LANGUAGES PFS 109.50 TARTURIANS 29.95 PFS: REPORT 109.50 GOBLINS 29.95 GRAFPAK 95.00 VISICALC 3.3 219.50 CREATURE VENTURE 29.95 EXPEDITER COMPILER 109.50 VISIPLOT/TREND 295,00 WIZARDRY 49.95 HAYDEN COMPILER 195.00 VISIDEX 219.50 ALKEMSTONE 43.95 TASC (MICROSOFT COMPILER) 195.00 VISITERM 175.00 KAVES OF KARKHAN 43.95 TRANSFORTH I 135.00 VISIFILE 275.00 SORCEROR OF SIRA 31.95 ALD SYSTEM I! 135,00 DESKTOP PLAN II 219.50 ODYSSEY 29.95 APPLE PILOT 175.00 TARGET BUSINESS PLANNER 249.95 DUNGEON CAMPAIGN/ APPLE FORTRAN 220.00 REAL ESTATE ANALYSER 175.00 WILDERNESS 34.95 MICROSOFT FORTRAN 220,00 CONTEXT CONNECTOR 195.00 SARGON It 37.95 FORTH tt 99.50 THE GENERAL MANAGER 109.95 BACKGAMMON 31.95 SUPERKRAM 179.50 WINCHENDON STATISTICS 220.00 BRIDGE 29.95 PHIL’S CHEAP EDITOR 59.95 DB MASTER 245.00 MONOPOLY 44.95 TINY PASCAL. 54.95 DB UTILITY PAK #1 109.95 HI-RES GOLF 32.95 LISA ASSEMBLER 2.0 62.50 WORDSTAR 349.50 LISP 109,95 SPELLSTAR 165.00 ACTION AND ARCADE GAMES MONITOR EXTENDER 2750 SANDY'S WORD PROCESSOR 175.00 DISK FIXER 32.95 RASTER BLASTER 32.95 DOSOURCE 3.3 49.95 SPELLBINDER 495.00 POOL 15 37.50 TELLSTAR 85.00 THE WORD 99.50 GORGON 42:95 APPLE—CILLIN 49.95 SUPERSCRIBE "1 139.95 APPLEOIDS 32.95 ACTION SOUNDS & HIRES THE DICTIONARY 109.95 PHANTOMS FIVE 37.50 SCROLLING 24.95 SCHOOL TIMETABLE 49.95 SPACE EGGS 32.95 ASCII EXPRESS 79.50 TIME MANAGEMENT 195.00 STAR THIEF 32.95 Z—TERM 169.95 MICRO MEMO 39.95 FALCONS 32.95 THE SOURCE 140.00 CORP SYSTEM 190.00 APPLE PANIC 32.95 VISITERM 175.00 DBASE 11 700.00 SNOGGLE 2995 HEAD ON 2750 BOOKS EDUCATION INTERNATIONAL GRAND PRIX 32.95 AUTOBAHN 32.95 ASSEMBLY LANGUAGE 19.95 ‘APPLE PILOT 175.00 FENDER BENDER 29.95 @ BENEATH APPLE DOS 24.95 FRACTIONS 39.95 HIRES SOCCER 34.95 APPLE I USERS GUIDE 19.95 DECIMALS 39.95 MISSILE DEFENSE 32.95 @APPLE MACHINE LANGUAGE — 17.0 ARITHMETIC SKILLS 49.95 BILL BUDGE SPACE ALBUM 44.95 MOSTLY BASIC 17:50 COMPU—SPELL. 39.95 EPOCH 37.50 PASCAL PROGRAMMING (LEWIS) 17.50 ELEMENTARY MATHEMATICS SNEAKERS 32.50 APPLESOFT LANGUAGE 2.95 VOL1 19.95 PULSAR 32.95 APPLE BASIC FOR BUSINESS. 19.95 CARTELS & CUTTHROATS 43.95 STAR CRUISER 2995 @ COMPUTER GRAPHICS PRIMER 19.95. SENTENCE DIAGRAMMING 24.95 ORBITRON 32.95 SHAKE HANDS WITH THE APPLE 12.50 THE LINGUIST 39.95 OUTPOST 32.95 CYBER STRIKE 43.95 SUBSCRIPTIONS SIMULATIONS AND ADVENTURES COPTS & ROBBERS 32.95 SPACE QUARKS 32.95 INFOWORLD (WEEKLY AIRMAIL) 120. FLIGHT SIMULATOR 34.95 SPACE RAIDERS 32.95 THREE MILE ISLAND 41.95 ABM 29.95 SUBSCRIPTIONS WARP FACTOR 43.95 GENETIC DRIFT 32.95 OPERATION APOCALYPSE 64.95 TRACK ATTACK 32.95 INFOWORLD SHATTERED ALLIANCE 64.95 BUG ATTACK 32.95 (WEEKLY AIRMAIL) 120.00 For our free catalogue send the attached coupon or write to: MICRO—EDUCATIONAL, 17 PARK ROAD, GARDEN SUBURB, NSW 2288. APC 97 FOR SALE DUMB TERMINALS AT DUMB PRICES WE HAVE SEVERAL ADI/ADMIA LEAR SIEGLER COMPUTER TERMINALS RS 232 FOR SALE AT $750 EACH ONO Telephone TOM or BARRY (02) 212 1399 After hours (02) 969 6444 Computer Focus GREAT VALUE BUSINESS SYSTEMS OR START UP FAMILY PACKS on SPECTACULAR REDUCTION! EPSON MX—100 PRINTER $1049.00 + 17.5% sales Tax* To Order: Send Bank Cheque, Money Order or, Personal Cheque or Purchase orders from qualified institutions to Computerware address Allow up to 4 weeks delivery Shipping: Road delivery, others specify. Freight & Insurance collect. * if applicable. FROM Authorised Dealers Computerware Full Computer Service Sorte, 602 i{eley.) Business Professional Home MELBOURNE, 3000. 4/224 George Street, Liverpool, NSW (02) 600 8222 WE ALSO SELL: ay 1 Sereno Processor rege YOUR SOURCE ON THE re Report $110.00 age os wasnt MORNINGTON PENINSULA ane SOURCE AMERICAN SOURCE PLEASE SEND DETAILS TO. $160 -| COMPUTERS 2000 ‘) bankcard se 1 ISLAND VIEW ROAD, TYABB, VIC. 3913. welcomehere .. Postcode ...... PHONE: (059) 774 617 9AM—9PM BANKCARD No AT LAST. A SIMPLE, EFFECTIVE, AUSTRALIAN WRITTEN DEBTORS SYSTEM sysohale cree FOR YOUR APPLE. COMPUTERS 2000 TISLAND VIEW DRIVE TYABB 3913 Runs on 48K, 40 Col Screen 059774617 SAM-9PM 1 or 2 Disk Drives & Printer APC 111 MICROPROGRAMMING/MICROVOICE CONSULTANT, REPAIRS, MODIFICATIONS, SOFTWARE SUPPORT, EPROM Programming. Turn your SYSTEM 80 or TRS80* into a real computer 1. Lower case with descenders. Extra characters can be added on request such as Greek, Chinese or French or Card Suits. 2. Reverse image on one or more letters. Simple to program in BASIC or ASSEMBLER. 3. Double your CPU speed. A must for tape users. Save or load programs in half the normal time. Great for speeding up thinking games or those slow Basic programs. Works with Disk in- cluding double density using NEWDOS80”’. Complete kit assembled and tested $69.00. Comes with full installation instructions or we will install for $25.00. Reverse image & fast speed only $52.00. Add $2.50 for P & P. MICROPROGRAMMING, P.O. BOX 475, MOUNT WAVERLEY, VICTORIA 3149. or ring (03) 233 6280 for more details. . * Trade mark of Tandy Corp. " Trade mark of Apparat Inc DAMAR mo 7 MANAGEMENT SYSTEMS The HP 125 Business Assistant A personal office computer for: Integrated General Accounting Word Processing Financial Decision making Graphics Presentations Budgeting Data Communications _ Forecasting THE CP/M SOLUTIONS MACHINE AVAILABLE EX STOCK FOR IMMEDIATE DELIVERY For further information or an obligation free demonstration call or write now to: OAMAR MANAGEMENT SYSTEMS 14 Cedar Grove, HIGHTON, 3216 Victoria Telephone (052) 61 3178 (052) 43 1445 Word Processors from $4,500 to $9,000 (inc S Tax) Professionals buy their Word Processor/Computers from COMPUTER GALERIE The new 64K Apple || PLUS is a managerial computer. It has the full range of SIX-S BUSINESS PROGRAMS* to help you solve your problems. * Fully supported quality Aust- ralian software. Invoicing, Stock Control, Word Processing, Cash Flow, Forecasting, Payroll. aes AND NOW HAVE THE REVOLUTIONARY Epson ert type 1 Low cost printer e = Tack-sharp 80 or 132 columns e Letterhead forms e@ Super graphics call David Diprose BUSINESS DIVISION COMPUTER GALERIE 66 Walker Street NORTH SYDNEY 929 5497 y,